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MOST IMPORTANT SCIENCE VIGYAN GENERAL KNOWLEDGE GK REVISION SUMMARY GIST NOTES FOR ALL COMPETITIVE EXAMS 

Physics

IMPORTANT SUMMARY

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Measurement/Unit

  • In the field of Physics Watt is measurement of power, describing the rate at which electricity is being used at a specific moment.

  • The S.I. unit of power is watt, which is equal to joule per second. Power is always represented in watt (W) or Kilowatt (KW).

  • The S.I. unit of Force is ‘Newton’ or kg. m/sec2

Force = mass × acceleration

  • In physics, something the causes a change in the motion of an object is called force. The modern definition of force (an object’s mass multiplied by it’s acceleration) was given by Isaac Newton in Newton’s Law of motion.

  • When a force acts to move an object, then work done by the force is equivalent to the product of force and displacement in the direction of force. It is a scalar quantity. The S.I. unit of work is Newton meter, which is also called as Joule. Joule is also the unit of Energy.

  • Electrical resistivity is an intrinsic property that quantifies how strongly a given material opposes the flow of electric current. A low resistivity indicates a material, that readily allows the movement of electric charge. The S.I. unit of electrical resistivity is ohm-meter (Ω). It is commonly represented by the-

Greek letter ρ, rho. Defined as

Here,

R = electrical resistance of material.

L = Length, A = Cross section Area ρ = resistivity

Faraday is the S.I. unit of Capacitance, Volt is the S.I. unit of Electric Potential, Ampere is the unit of Electric Current While Ohm is the S.I. unit of Electrical Resistance (not resistivity).

  • Light year is a unit of astronomical distance equivalent to the distance the light travels in one year, which is 9.46 × 1015

  • A PARSEC is a unit of length used to measure the astronomically large distance of objects beyond our Solar System.

1 PARSEC = 3 × 1016 meters

1 Light year = 9.46 × 1015 meters

So, 1 PARSEC = 3.262 light-years,

  • 1 Centimeter = 0.39 inch, so we can multiply centimeter by 0.39 to convert it to ‘inches’.

  • 1 nanometer = 10-9 meter

1 Feet = 0.305 meter

1 Feet = 30.5 × 107 nanometer

6 Feet = 6 × 30.5 × 107 nanometer

             = 183 ×107 nanometer

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  • Ampere is a unit to measure electric current. If one Ampere current is flowing in any conducting wire, if means 6.25 × 1018 electrons are entering per second from one direction and same amount of electrons flows from the other end per second.

  • Megawatt is the measuring unit of power, which is generated in Power station or Power Plant. 1 Megawatt is equal to 106 (million) watt.

  • Acceleration is the rate of change of velocity of an object, with respect to time. The S.I. unit of acceleration is the meter per second square (m/s2). The S.I. unit of force is Newton (N). The S.I. unit of Impulse is the Newton Second (N.S.). The S.I. unit of Work is Joule.

  • Pascal is the unit of pressure or stress in the International System of Units (SI). Dyne is unit of force in CGS system.

  • The SI unit of power is the Watt (w), which is equal to one joule per second. Knot is the unit of measuring of speed of a ship. Nautical mile is a unit of distance used by navigators in sea. Calorie is a unit of measuring heat and energy.

  • Joule is the SI unit of work. Ampere, Watt, Volt and Calorie are the units of Current, Power, Electric potential and heat respectively.

  • Light year is not a unit of measuring time, but a unit of measuring distance.

  • Horse power is a unit of measurement of power (the rate at which works is done).

1 Watt = 1 Joule/second

1 Horse power = 746 Watt.

  • In fluid mechanics, the Mach number is a dimensionless quantity representing the ratio of the speed of a body to the speed of sound in the surrounding medium. Supersonic travel is a rate of an object that exceeds the speed of sound (Mach 1). So Mach is used to represent the high speed. Wavelength is measured in Angstrom while pressure is measured in Pascal and energy in Joule.

  • 1 micron = 10-6

 = 10-6× 10-3 mm.

 =  mm.

 =  mm.

  • One micron represents a length of 10-6 It is represented by µ sign.

1 micron = 0.000001 m. = 0.0001 cm.

 =    cm. =  cm. = 10-4 cm.

  • Celsius is a scale and unit of measurement for temperature. Heat is measured in Calories. Nautical mile is used to measure distance at sea. 1 nautical mile is equal to 1.852 km. The S.I. unit of power is Watt (w), which is equal to Joule per second. Another unit of power includes horsepower (hp) or metric horsepower. 1 horsepower is equal to 746 watts. Decibel is used to measure the sound intensity.

  • The watt is a derived unit of power in the International System of Units (SI).

  • The SI unit for distance is meter. 1 km. is equal to 1000m. 1 m. is equal to 100 cm.

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  • The smaller units of measuring mass are Milligram, Microgram, Pikogram and Femtogram.

1 Pikogram = 10-12 gram                       

1 Milligram = 10-3 gram

1 Microgram = 10-6 gram                     

1 Nanogram = 10-9 gram

1 Femtogram = 10-15 gram

  • The Pascal (Pa) is the unit of Pressure or Stress in the international system of units (S.I.). It is named after the scientist Blaise Pascal. One pascal is equal to one Newton (N) of force applied over an area of one square meter (1 m2).

1 Pa = 1 newton/ meter2 =1 kg/ms2

  • Bar is metric (but not SI) unit of pressure. It is equal to 105 newton/ meter2. Pascal is SI unit of pressure. Or 1 bar = 105

  • 1 Dyne = 1.02 × 106

And 1 Bar = 106 dyne/cm2

Therefore substituting the value of Dyne into the value of Bar  ̶

1 Bar = 106 dyne/cm2 = 1.02 × 106 Kg/cm2,

= 1.02 Kg/cm2.

  • The amount of oil is measured in cubic meters.

1 barrel = 158.9873 litre

1 barrel = 0.158987 cubic  meter

1 barrel = 42 U.S. gallon

1 barrel = 34.9723 U.K. gallons

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  • 1 Micron = 10-6 meter

1 Nanometer = 10-9 meter

1 Angstrom = 10-10 meter

1 Fermi meter = 10-15 meter

  • Nanometer is a unit of length in the metric system, which is equivalent to 1 × 10-9

  • Cusec is a measure of flow rate and is informal shorthand for “cubic feet per second” (28.317 litres per second). Byte is a unit of digital information in computing and communications that consists of eight bits. The Richter magnitude scale (also Richter scale) assigns a magnitude number to quantify the energy released by an earthquake. The bar is a metric (but not SI) unit of pressure exactly equal to 100,000 Pascal.

  • Cusec (Cubic feet per second) is a unit of measuring the flow of water.

  • Ozone layer thickness is expressed in terms of Dobson units, which measure, what its physical thickness would be if compressed in the earth’s atmosphere. 1 Dobson unit is defined to be o.o1 mm thickness at STP (Standard Temperature and Pressure). The unit is named after G.M.D. Dobson, one of the first scientists to investigate atmospheric Ozone. One Dobson unit is the equivalent to 2.69 × 1016 molecules of ozone per square centi meter.

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Measuring Dev ice and Scales

  • SONAR [Sound Navigation and Ranging] is used for locating submerged objects in an ocean. It is based on a very simple principle i.e. pulse of ultrasonic waves is sent into the water, it strikes the target and bounced back towards the source. It helps to detect or locate submerge submarines and icebergs.

  • SONAR is mostly used by Navigataors.

  • An Audiometer is used to measure the intensity of sound, while Anemometer is used for measuring wind speed. Chronometer is a timepiece or timing device with a special mechanism for ensuring and adjusting its accuracy, for use in determining longitude at sea or any purpose where very exact measurement of time is required. Audio phone is an instrument which placed against the teeth, conveys sound to the auditory nerve and enables the deaf to hear more or less distinctly.

  • A Tacheometer is a type of theodolite used for rapid measurements and determines electronically or electro-optically the distance to target and is highly automated in its operations. The remaining pairs are correctly matched. Pyrometer is a device used for measuring relatively high temperature, such as is encountered in furnaces. Anemometer is a device used for measuring wind speed. An Ammeter is a measuring instrument used to measure electric current in a circuit. Electric current is measured in Ampere (A).

  • A Pyrometer is a type of remote-sensing thermometer which is used to measure high temperature. It is based on Stefan-Boltzmann law, which describes that the total radiation emitted by a black body is proportional to the fourth power of its absolute temperature (E T4). It is also used to measure the temperature of distant objects such as sun.

  • A pyrometer is a type of remote sensing thermometer used to measure the temperature of a surface. In the modern us- age, it is a device that from a distance determines the temperature of a surface from the spectrum of the thermal radiation it emits, a process known as pyrometry.

  • A total radiation pyrometer is used to measure very high temperature. It is suited especially for the measurement of moving objects or any surface that cannot be reached or cannot be touched. The temperature is measured by measuring the thermal radiation.

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  • Mainly there are two types of devices that are used to measure solar radiations these are:

  • Pyrheliometer

  • Manometer is an instrument that uses a column of liquid to measure pressure, commonly referred as pressure measuring instrument.

  • Ammeter is an instrument used to measure the electric current not for measuring electric power.

  • A barometer is a scientific instrument used in meteorology to measure atmospheric pressure. A sudden fall of mercury in a barometer indicates the thunderstorm.

  • A barometer is an instrument for measuring atmospheric pressure. A simple barometer consists of a long glass tube (closed at one end and open at the other) filled with mercury and turned upside down into a container of mercury.

  • Lactometer is used for the measurement of the density of milk. Buryrometer is used to measure fat content in milk or milk products.

  • Hygrometer is a device used to determine the humidity of the atmosphere. Lactometer is used to measure the density of milk. Hydrometer is used for measuring the water vapour content of the atmosphere while Potentiometer is used to measure the potential (voltage) in a circuit.

  • A hygrometer is an instrument used to measure the moisture content in the atmosphere which is also called as humidity in the air. Spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum. A Eudiometer is a laboratory device that measures the change in volume of a gas mixture following a physical or chemical change.

  • Hygrometer is device which quantifies the humidity in the air. Pyrometer is used for high temperature and Hypsometer is used to measure height or attitude. Thermostat is a device which is used for regulating the temperature of a system so that the system’s temperature is maintained near a desired set point temperature.

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  • Thermo resistor is a device which acts as an electronic thermometer. This device changes its resistance with changes in temperature..

  • Pyrometer is used to measure temperature above 1500°

  • Luxmeter is used to measure the intensity of light, while colorimeter is a device used to measure the intensity of colour.

  • RADAR stands for Radio Detecting and Ranging. As indicated by the name, it is based on the use of radio waves. It refers to the technique of using radio waves to detect the presence of objects. Today, it is used for a wide variety of applications, such as determine the range, angle or velocity of objects.

  • The Richter scale is the most common standard of measurement for an earthquake. It was invented in 1935 by Charles F. Richter of the California Institute of Technology as a mathematical device to compose the size of earthquake. The Richter scale is used to rate the magnitude of an earthquake, that is the amount of energy released during an earthquake.

  • Richter scale is not used to measure humidity. In fact, it is used to measure the intensity of earthquake.

  • Earthquake generates seismic waves which can be detected with a sensitive instrument called Seismograph. Crescograph is a device for measuring growth in plants. It was invented by Sir Jagadish Chandra Bose in 1900 AD. Raingauge is used to measure rain. Geiger Counter is a device that detects radioactivity or radiation.

  • An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. Ammeter is used to measure electric current in a circuit. A Seismograph is used to measure earthquakes and Ohm is an electrical unit of resistance.

  • Fathometer is an instrument used to determine the depth of water or a submerged object by means of ultrasound waves. The barometer is used to measure atmospheric pressure. Hygrometer is used to measure atmospheric moisture and Altimeter is used to measure altitude/height of an object above a fixed level.

  • Anemometer :                 Wind velocity

Seismograph               :                 Earthquake

Barograph                   :                 Atmospheric pressure

Hygrometer                 :                 Humidity

  • Seismometer is an instrument used to measure seismic waves generated by earthquakes. Carburetor is a device that blends air and fuel for an internal combustion engine. Cardiograph is an instrument used to record the mechanical movements of the heart. Manometer is an instrument that uses a column of liquid to measure pressure.

  • Phonometer is an instrument which is used for testing the force of the human voice in speaking.

  • A Polygraph popularly referred to as a lie detector, measures and records several physiological indices such as blood pressure, pulse, respiration, and skin conductivity while the subject is asked and answers a series of questions. A Pyrometer is a type of remote-sensing thermometer used to measure the temperature of a surface. A Gyroscope is a spinning wheel or disc in which the axis of rotation is free to assume any orientation. Kymograph is an instrument for recording variations in pressure, as of the blood or in tension, as of a muscle, by means of a pen or stylus that marks a rotating drum.

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Mechanics

 

  • A simple machine helps a person in doing the same amount of work with less force.

  • The reading of the balance increases if the person inhales deeply.

  • The working principle of a washing machine is based on centrifugation force. The term centrifugal force is used to refer to an inertial force, particle moving on a circular path that has the same magnitude and dimensions as the force that keeps the particle on its circular path but the point in the opposite direction.

  • A vector quantity is a quantity that is fully described by both magnitude and direction. On the other hand, a scalar quantity is a quantity that is fully described by its magnitude. Thus displacement, velocity and force are the examples of vector quantity while volume is a scalar quantity.

  • Momentum is a vector quantity.

  • Momentum is a vector quantity that is the product of Mass and the Velocity of an object or particle.

Momentum = Mass × Velocity

So,             Mass =

  • A force can cause an object with mass to change its velocity i.e., (which includes to start moving from a state of rest) to accelerate.

Force = Mass × Acceleration = m.a

  • Volume of a cube = l3 (where l is the length of cube’s edge)

Surface area of cube = 6l2

According to question, both are equal to each other Therefore l3 = 6 l2

Hence l = 6

  • Energy conservation refers to the reducing of energy consumption through using less of an energy service. The Law means that energy can neither be created nor destroyed.

  • The kinetic energy is the energy in moving objects or mass. The kinetic energy of the wind (wind energy) can be converted into electrical or mechanical energy.

  • The term wind energy or wind power describes the process by which the wind is used to generate mechanical power or electricity. Wind is used to generate mechanical power or electricity Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks such as grinding grain or pumping water or a generator can convert this mechanical power into electricity.

  • According to the Newton’s first law of motion sometimes referred to as the law of inertia which states that an object at rest stays at rest and in motion remain in motion with same speed and in the same direction unless acted upon by an unbalanced force. When a train suddenly starts, the passenger tends to fall backward. This is because the lower part of the body which is in contact with the train begins to move while the upper part of the body tends to maintain its position. As a result, the upper part tends to fall backward.

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  • Movement is not possible on any frictionless surface as friction is required for movement. Momentum is the property that a moving object has due to its mass and motion. Hence, when there is no external force applied on any moving object, its momentum cannot change.

  • It is very difficult to walk on the ice than on the road because ice has a lesser friction than the road. The roughness of road’s surface gives you much frictional force which enables you to move forward on road.

  • The static friction that holds an object in place is greater than the kinetic friction that slows down a moving object. In other words, once you start an object moving, the friction decreases from the static friction holding the object in place. You have seen this in trying to slide a heavy box across the floor. It may be very difficult to move, but once it starts sliding, it is easier to push.

  • Let the mass of the person is M and the mass of the boat is N, then momentum of boat + momentum of person before Jump = 0

Then Momentum of both after man’s jump = M × 5 – N × 0

M × 5 – N × 0.5 = 0 (According to the principle of conservation of momentum)

 N × 0.5 = M × 5  =  = 10

Thus mass of the boat is 10 times greater than that of the man.

  • If the objects have equal kinetic energy and if equal stopping force is applied on them, then they would stop at the same distance.

  • Dynamic friction of any object is proportional to adhesion reaction and less than static friction. Thus, option (b) is the correct answer.

  • When an oil tanker is partially filled with oil and moves forward on a level road with uniform acceleration, the free surface of oil then assumes parabolic curve.

  • tan θ

θ = Inclination from normal

r = Radius of the circular path

v = Velocity to vehicle

If a four wheeler is moving faster than the relative speed then it skids outwards but then the frictional force provides the necessary centripetal force which ensures the car to have a curved path.

  • As we know v = u + at or at = v – u

 a =

       Where, v = ultimate velocity of the particle

         U = initial velocity of the particle

         a = Acceleration, t = time

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Motion under Gravity

  • Brahmagupta was a great 7th century mathematician and astronomer. He was born in Bhinmal in Rajasthan. He is best known for his’ Brahmasphuta Siddhanta’ in which he declared that all the things gravitate to the earth.

  • In 1687, Isaac Newton published his Law of Gravitation in “Mathematical Principles of Natural Philosophy”. Newton proposed that everybody in the universe is attracted to every other body with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In term of mathematical relationships, Newton’s law of Gravitation states that the Gravitational Force (F) between two particles of mass m1, and m2 has a magnitude of : F =

Where, r = the distance between both the masses, G = Gravitational constant.

  • In space, astronauts can’t stand erect because there is no gravity or microgravity. In this condition people or objects appear to be weightless. Microgravity affects the human body in several ways. For example muscles and bones can become weaker without gravity.

  • If an apple is released from an orbiting spaceship, it will move along with the spaceship at the same speed.

  • Anything will remain stable as long as the vertical line through the centre of gravity falls within its base. The centre of gravity is that point whole mass of the body is supposed to be concentrated. Till today the vertical line from the centre of gravity has been falling within the base of this tower. That is why it has not fallen. It is believed that when the tower leans further and the line from its centre of gravity passes out of its base, it will fall down.

  • Let the present distance between the earth and the sun is ‘r’ then according to the Newton’s universal law of gravitation. The gravitational force imposed by the Sun on the Earth:

F1 = G                                                                                                          ……………… (1)

S = Mass of                           

ME = Mass of Earth                                                                                            

G = Gravitational constant

If the distance between the Earth and the sun were twice, then,

F2 = G  = G                                                                                        ……………….(2)

from equation (1) and (2)

                         4F2 = F1

  F2 =  F1

  • If an object is falling from above, its weight remains same because mass of the object and the gravity remains unchanged.

  • All pieces of equal size of woods, wax and iron falling from same height despite their weight difference will hit the ground at the same time because the same gravitational acceleration (g) applies to all object.

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  • If there is no resistance from the air, both the balls will hit the ground at the same time. But in the presence of air, the heavier things fall faster than the lighter things. The resistance from air slows down the fall of lighter things.

  • The Moon is the Earth’s only natural satellite. The surface gravity of the moon is only 1/6 that of the Earth. So the weight of a human will be 1/6 of the that on the earth.

  • At a given place, the value of acceleration due to gravity is constant but it varies from one place to another place on the earth surface. It is due to this fact that earth is not a perfect sphere. It is flattened at the poles and bulges out at the equator (ellipsoidal shaped).

In this figure, the polar radius Rp is not equal to the equatorial radius Re. Now,

g =

Now, as ‘G’ & ‘M’ remain constant, therefore

g

Thus the value of ‘g’ is minimum at equator and maximum at the poles. It means ‘g’ increases as we move 90 from the equator to poles.

  • For an object falling freely from the state of rest under the gravitational acceleration, the equation of motion is

S = gt2, which is also an equation of the parabola.

The body is placed on the smooth plane inclined, thus if moves under g sin θ instead of g and we know that it starts moving from rest, therefore initial speed

u = 0

The equation of motion s = ut + gt2

Hence l= gsinθ.t2

 = t2 ….(i)        

Now as we know  sin θ =  l =  putting this value of l in equation (i), we get

                  t2 =

                   t =

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  • The acceleration due to gravity of a catastrophic earthquake will be greater than 980 cm/sec2or 9.8 m/sec2.

  • The mass of a body does not change with respect to gravity. It is the weight that changes due to increase or decrease in gravity. So the mass of body will remain the same as on the moon as it was on the Earth.

  • The phenomenon of weightlessness occurs when there is no force to support on your body. When your body is effectively in “free fall”, accelerating downwards at the acceleration of gravity, then you are not being supported. The sensation of apparent weight comes from the support that you feel from the floor, from the seat etc. The term ‘zero gravity’ is often used to describe such condition.

  • Radium is chemical element discovered by Marie Curie and her husband Pierre Curie on 21 December, 1898. Penicillin was discovered by Alexander Fleming in 1928. X-rays were discovered by William Roentgen in 1895 while experimenting with a cathode radiation, Edward Jenner is well known around the world for his innovative contribution to immunization and the ultimate eradication of smallpox.

  • The Earth spins and moves through space in an orbit around the sun. We don’t “feel” this movement because we are spinning and moving through space with the earth. Since we are standing on the earth, we move as much (and as fast) as the earth moves. One way to recognize the earth’s movement is to look at objects that are not attached to earth: like the sun or stars. For example, if we are in a car which is moving at a constant speed on a smooth surface, we will not feel its motion. However, when the car accelerates or when the brakes are applied, we do feel the motion.

  • If the gravitational force of the earth suddenly disappears, then the weight of an object will become zero but the mass will remain the same.

  • There are two factors associated with the ability of a satellite to remain in its orbit around the earth. The first is that the satellite was accelerated by the launch vehicle. The second factor is the gravitational attraction of the earth which produces the necessary acceleration for its motion in a curved path.

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  • There is only one main force acting on a satellite when it is in orbit and that is the gravitational force exerted on the satellite by the earth and the centrifugal force necessary to maintain the orbit of the satellite.

  • Centripetal force is a real force that counteracts the centrifugal force and prevents the object from “flying out,” keeping it moving instead with a uniform speed along a circular path. Gravity is the centripetal force that keeps planets moving around the sun and satellites moving around planets.

  • Gravitation force is the weakest force holds the position of strongest force among them.

  • Let the mass of the person is m and weight is w and the elevator going upward with acceleration the force due to gravity = mg

  • the force giving the acceleration = ma

According to Newton’s second law-

w – mg = ma

w = m(g + a)

So, it is clear that when the elevator is going upwords a person actually feels a   little heavier than his usual weight and on the other hand when elevator accelerates downward then a person feels a little reduction than his usual weight.

  • A batsman hits a cricket ball which then rolls on a level ground. After covering a short distance, the ball comes to rest because there is an external force i.e. frictional force acting on the moving ball opposing its motion. If there is no frictional force then the ball will roll continuously.

  • The time period of a pendulum depends on its length. As we know that T = 2π , thus the result is that the one variable that affects the period of the pendulum is the length of the string. Increases in the length lead to increases in the period.

  • Time period of simple pendulum T = 2π

Where l = length of the pendulum

In summer, the length of the pendulum is slightly increased. Due to this the time-period also increased. Thus result that the pendulum clocks are slow in summer.

  • A girl is swinging on a swing in sitting position but when she stands up, she is effectively moving her mass higher, thus shortening the length of the pendulum. Shortening this length will decrease the period or the period of the swing will be shorter.

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  • When an object, which is in simple periodic motion passes through it mean;

  1. No force acts on it.

  2. It’s acceleration becomes zero

  3. Maximum velocity

  4. Potential energy is zero

  • When the object reaches the position of extreme/peace speed then,

  1. Its acceleration is maximum

  2. Counterforce acting on that is maximum.

  3. It’s Kinetic energy is zero.

  4. Has maximum potential energy.

  5. Has zero velocity.

In each rotation, the pendulum twice attains a specific velocity.

In addition, under normal circumstances oscillation of usual pendulum decreases with time

A pendulum clock runs faster in winter because in winter the length of the pendulum or the swing become smaller due to contraction and the clock begin to run fast.

  • The term escape velocity means the minimum speed that a moving object must have to escape from the gravitational field of a celestial body and move outward into space. The escape velocity of earth is 11.2 km/sec.

  • 2 km/sec is the escape velocity of the earth which is minimum speed that is required to escape the earth’s gravity. If an object thrown is less than this, it will return to earth.

  • Moon has no atmosphere because the value of acceleration due to gravity g on the surface of the moon is small. Therefore, the value of escape velocity on the surface of the moon is small. The value of root mean square velocity of the molecules of different gases is much above the value of escape velocity on the moon. That is why all the molecules of gases escaped and there is no atmosphere on the moon.

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Physical Properties of Materials

  • The shape of a drop of rain is constrained by the surface tension, which tries to give it the shape for which the surface area is minimum for the given volume. The spherical shape has the minimum surface area. That’s why rain drops acquire spherical shape.

  • Friction is the most important property of nanomaterial.

  • Oil spreads on water surface because the surface tension of oil is less than water.

  • Kerosene oil floats on water because its density is less than the density of water.

  • Soap bubbles are large because when soap dissolved in water its surface tension is reduced. The pressure inside a soap bubble is more than atmospheric pressure.

  • The excess pressure inside the soap bubble is inversely proportional to the radius of soap bubble i.e. p . When these two bubbles are connected by a tube, the air will flow from smaller bubble to bigger bubble due to the fact that small bubble having smaller radius will exert more pressure. Hence the bigger bubble would grow at the expense of the smaller one.

  • Pollutants are made up of soot, dust or smoke particles, which is measured by particular yard stick called as Respirable. Suspended Particulate Matter (R.S.P.M.).R.S.P.M. is generally classified as PM 10 (diameter 10-2.5 microns) and PM 2.5 (under 2.5 microns). The smaller PM 2.5 affects the lungs and the air passage the most whereas the PM 10 affects the upper respiratory tract from the nose and windpipe.

  • All the four wires are made up of the same material, therefore, they have the equal Youngs modulus (modulus of elasticity)

Y =  =  =

                 

Thus, elongation of these wires is proportional to their length and inversely proportional to the square of diameter.

  • Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of, or even in opposition to external forces like gravity. Kerosene rises in the wick of the lamp through capillary action. If a person wants to consume the soft drink, he needs to impose some external force by his mouth. As we know capillary action takes place only in the absence of any external force, hence one would not be able to use a straw. Blotting paper also works on the principle of capillary action. It has a large number of pores on its surface which acts like a capillary tube. Nature is an excellent user of capillary action. The fine roots of trees act as capillary tubes, which provides them useful nutrients and water.

  • We can find several examples of capillarity in our daily life, such as blotting soft ink by blotting paper, rising of underground water, the spread of water drop on a cotton cloth, rising of kerosene in the wick of the lamp. But capillarity is not the only reason for rising of water from the roots of a plant to its foliage, apart from this transpiration and cohesion is also responsible for this process.

  • Viscosity is measure of the resistance of a fluid which is being deformed by either shear stress or tensile stress. In everyday terms, viscosity is “thickness” or “internal friction”. Viscosity of liquid (water) at different temperatures up to the normal boiling point is listed below.

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Temperature [°C]                                Viscosity [mPa.s]

10                                                           1.308

20                                                           1.002

30                                                           0.7978

40                                                           0.6531

50                                                           0.5471

60                                                           0.4668

70                                                           0.4044

80                                                          0.3550

90                                                           0.3150

100                                                         0.2822

Thus it is clear that with the rise of temperature, the viscosity of liquid decreases.

  • Kerosene oil rising in the wick of the stove is due to the surface tension of oil. The wick of the lamp has many holes which act as capillaries. So kerosene keeps on rising in the capillaries.

  • In a capillary tube, liquid rises in proportion with its surface tension would gain more height.

  • When a air bubble at the bottom of the lake rises to the top, it will increase in size. The pressure of the trapped air in the bubble decreases due to decreasing vertical liquid depth.

  • The fountain pen leak at high altitudes. If is because of low air pressure compared to the low atmospheric pressure outside at high altitude, so ink flows out of the pen.

  • Hydraulic brake, hydraulic press, hydraulic elevator all works on the principle of Pascal’s law which states that pressure exerted anywhere in a confined incompressible fluid is transmitted equally in all directions throughout the fluid such that the pressure variations remain the same.

  • Mobile and Automobiles have brought about a great revolution in the social life of Indians, where mobiles help to connect the people and automobile help in mobilizing of the people.

  • A sudden fall in barometer reading indicates that the weather will be stormy.

  • In a streamlined motion, the speed of layers of liquid is lowest near the pipe. As moved away from the pipe, the motion of layers gradually increases.

  • Asphalt is also known as bitumen, is a sticky, black and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be refined product. The primary use of asphalt is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other uses are for bituminous waterproofing product, including the production of roofing felt and for sealing flat roofs. Generally, all liquids expand on heating, but water is an exception to this rule. If water is heated, its volume gradually decreases. (This decrease in volume continues till the temperature rises to 4 °) At temperatures over 4°C water starts expanding. It then keeps expanding with the further rise in temperature, till finally at 100°C and turns into steam. In other words, at 4°C, water has the least volume (occupies the least amount of space) and maximum density (is at its heaviest). This irregular expansion of water is called anomalous expansion. This anomalous expansion plays an important role by only freezing the upper layer in lakes and rivers. During winter months in colder countries, the outside or atmospheric temperature is very low – it drops to below freezing – and the upper layers of water in the lakes and ponds start cooling. When the temperature of the surface layers falls to 4 °C, the water body acquires maximum density and sinks down. The water that sinks down displaces water below, and the lower layers of water simultaneously rise up. This also gets cooled to 4°C and again sinks down. When the temperature of the water body finally goes below 4°C, the density or heaviness of water decreases and as a result water does not sink down. The surface water finally freezes at 0°C while the lower part still remains at 4°C. The light frozen layer of ice floats on top.

  • This is because of a phenomenon is known as winter stratification in water bodies. In the winter season, the water at the top layer of water bodies will be ice cold (0°C) and are gradually frozen. But still, the bottom layers will have liquid water and maintain a temperature (4°C) which supports the life there. Thus, fishes and other aquatic animals are saved from the frozen top layer of water.

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  • Density of an object depends on its mass and volume. Density can be found by using the equation:

Density =

  • If an unsaturated sugar solution is prepared by mixing 100 grams of sugar with half liter of water then volume of the solution remain constant.

  • The mass of any substance while heating remains the same however its volume increases. Thus, its density decreases. But water exhibits an anomalous expansion on cooling and contraction on heating within a specific range of temperature. When water at 0°C is heated, it is observer that it contracts between 0°C to 4°C, i.e. volume decreases and thus density increases. The volume of water is minimum at 4° Hence the density of water is maximum at 4°C.

  • The density of water increases with temperature but volume decreases. At 4°C, the volume of water is low and density is maximum. Conversion of Celsius in Kelvin

K = C + 273

    = 4+273 = 277

         So, the density of water is maximum at 277K.

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  • An iron ball floats on mercury but gets immersed in water because the relative density of mercury is greater than the relative density of iron. However iron has a higher density than water.

  • Relative density or specific gravity is defined as a ratio of the density of a particular substance with that of water. The relative of pure water is l. The substance having the relative density less than l will float in water, while substance having the relative density more than l will sink in water. The ship is designed in such a way that its effective density (m/v) is less than the density of water, so it floats upon the water. But the density of iron needle is much larger than the water.

  • An iron needle can float on water due to the surface tension of water because upward force on the needle due to surface tension balances the weight of the needle.

  • According to the Archimedes’s principle of flotation, object appears to be heavier in the air than inside the water or they appear to be less heavy in the water. It is because water exerts an upward force on the objects immersed in it. This reduction is equal to the weight of the fluid that body displaces.

  • The separation of cream from milk by churning is due to centrifugal force.

  • Clouds form when the invisible water vapour in the air condenses into visible water droplets. They are so small that the effect of gravity on them is negligible. Thus the clouds float in the atmosphere because of their low density.

  • Technetium is a chemical element with atomic number 43. It was the first artificially produced element. Technetium was isolated by Carlo Perrier and Emilio Segre in 1937.

  • When pure water changes into the ice at 4°C, the density of ice so formed is 1/9th of the density of water. Therefore, in pure water, 90% part of the ice must be below the surface of the water and remaining 10% part must be above the surface. Sea water has high density (salty) water but the ice formed by it is pure and not salty.

  • According to Archimedes principle, floating object displaces an amount of water equal to its own weight. Thus, the water level remains the same when the ice cube melts.

  • When the water is heated, its density decreases. The density of the water at 100°C is at the lowest, so the body will sink. Water density is maximum at 4°C, so the body will float.

  • It is easier to swim in sea water than in river because, the sea water contains salt which increases the density of water and also increases its up thrust so, the chances of sinking get reduced and one can easily swim in such water.

  • When a ship enters a sea from a river, the ship is elevated due to the higher density of salty sea water than the river.

  • Statics is a branch of mechanics associated with the situation of rest.

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Light

  • About 98% of the radiation emitted the sun is in the range of 300 to 3000 nm (SR). Ultraviolet radiation (UV; 10 nm to 400 nm) has the highest energy content per quantum (Shortest Wavelength).

  • The electromagnetic spectrum encompasses all type of radiations. The part of the spectrum that reaches earth from the sup is between 100 nm to 106 This band is broken into three ranges – Infrared (above 700 nm), Visible (400 to 700 nm), Ultraviolet (below 400 nm).

  • Visible light is that part of electromagnetic radiation which can be seen by human eyes. A normal human eye can see the electromagnetic radiation between 390-780 nm of wavelength.

  • Eye is most sensitive to yellow-green light that is light of wavelength 5500 .

  • The light has a dual nature, sometimes it behaves only as wave and sometimes as light. In the later part of the 19th century and in the beginning of 20th century, it was realized that black body radiation and the photoelectric effect can be understood only on the basis of particle model of light. Some experiments require light to be a wave, while others require light to be a particle. This led to the acceptance of dual nature of light.

  • Due to its very small wavelength, the light appears to travel in a straight line.

  • The speed of light in a vacuum is 3.00×108 m/s, while the speed of sound in vacuum is zero and in air 343 m/sec. The speed of light in glass is 2.0×108 m/s. The velocity of light always greater than the velocity of sound. The velocity of celestial objects and the rockets is quite low than the velocity of light.

  • The sunlight takes about 500 second or 8.5 minutes to reach to the earth.

  • When light passes from air to glass or one medium to another, then the frequency of the light remains constant but wavelength and velocity are changed.

  • Photosynthesis is the process used by the plants to convert light energy into chemical energy.

  • The neon gas is used in discharge lams, tubes and in fluorescent bulbs.

  • The formation of glittering colour in the thin from soap in the result of the phenomenon of total reflection and interference. When light waves hit bubble, some of them bounce straight back off the outer part of the soap film. Others refracted on through but then bounce of the inner part of the film. Now refracted and reflected gives soap foam glittering colour.

  • Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fibre.

  • Total internal reflection takes place when a ray of light is travelling from denser to thinner medium and angle of incidence is greater than the critical angle, the ray is completely reflected from the surface and meet each other as if the surface is a mirror.

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  • A cut diamond shines brilliantly due to total internal reflection of light. Diamond shines more than a glass piece because of its low conical angle 24.4 degrees. This if the reason why diamond shines more than a glass piece of same shape.

  • Endoscopes are widely used to examine the interior of a hollow organ or cavity of the body. They are based on the principle of total internal reflection within a fibre optic bundle of fibres.

  • An endoscope is a medical devices consisting of a long thin flexible (or rigid) tube which has a light source and a video camera. Images of the inside of the patient’s body can be seen on a screen. It is not suitable to categorize endoscope as a type of camera.

  • The refractive index of diamond is very high. Diamond achieves brilliance partially from total internal refraction. It has been cut or designed in such a way that if light enters in to it, incident light strikes many of the internal surfaces. After many such reflections, the colour in the light are separated and hence been individually.

  • The mirage is caused by the total internal reflection of light at layers of air of different densities. In Desert areas, the successive upper layer is denser than those below there.

  • Roster scam is used in CRT (Cathode Ray Tube) monitors, in which electronic beam is projected by electronic gun to general an image on the screen.

  • The size of the sun at dusk is an optical illusion. The sun appears smaller during noon but longer at dawn or more clearly at dusk. At dawn, the sun is seen with other objects on the horizon and looks big. The colour of the sun at dawn is also an optical illusion. Finally twinkling of stars is also an optical illusion caused by the refraction of light while moving through various layers of atmosphere.

  • Red, Green and blue are referred to as the primary colours of light. Because we add them together to create a colour, we call them additive colours. Cyan, Magenta and yellow are called the subractive colour because we create colour by using them to subtract colour from while light. If we add the pair of primary colours or subtractive colours we obtain white colour.

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  • As we all know the sunlight is a white light and it consists of seven colors. The splitting of light into its different components (VIBGYOR) i.e. violet, indigo, blue, green, yellow, orange and red is called the dispersion of light. A prism is used to disperse light into its different components.

  • The cathode ray tube (CRT), which is used in colour television uses three different phosphors which emit red, green and blue light respectively. They are packed together in stripes or clusters called “triads”.

  • The back of your eye is lined with a layer known as the retina. The retina operates in a similar way to the film inside a traditional (non-digital) camera. The part of the retina (known as the macula) takes care of your sharp vision. Your retina’s nerve cells change light rays into electrical impulses and then sends them to the brain though the optic nerve.

  • The colour of an opaque object is the same as the colour of the light that reflected by it. Opaque object doesn’t pass the light through. It absorbs part of incident light and reflects the other part.

  • The eye lens is composed of a fibrous, jelly-like material. Its curvature can modified to some extent by the ciliary muscles. The change in the curvature of the eye lens can thus change its focal length. When the Muscles are relaxed, the lens becomes thin. Thus its focal length increases. This enables us to see distant objects clearly. When you are looking at objects closer to the eye, the ciliary muscles contract. This increases the curvature of the eye lens. The eye lens then becomes thicker. Consequently, the focal length of the eye lens increases. This enables us to see nearby objects clearly.

  • Head Mirror is mostly used by doctors for the examination of ear, nose and throat. It comprises a circular concave mirror, with a small hole in the middle and is attached to a head-band.

  • Myopia or nearsightedness is a refractive error which means that the eye does not band or refract light properly to a single focus to see the image clearly. In Myopia, close objects look clear but distant objects appear blurred. It is corrected by using a concave lens.

  • A convex les is thicker in the middle and thinner at the edges. Rays of light that pass through the lens are brought closer together. A convex lens is also called a converging lens. A convex lens is also used in reading glasses & it also used to remove the defect of farsightedness.

  • A concave lens is used to remove the defect of Myopia.

  • The minimum height of plane mirror to enable a person to see full image is ½ of his height. According to the principle of reflection, the angle of incidence is equal to angle of refraction. When the ray of light travels from bottom to top a person and reaches his eyes then he is able to see the clear image.

  • Farsightedness (hyperopia) as it is medically termed is a vision condition in which distant object are usually seen clearly, but close one do not come into proper focus. To remove this vision problem one should use a convex lens.

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Thermodynamics

  • Steam at 1000 C causes more severe burns than the water at the same temperature because steam provides more heat. The boiling point of water is 100 degree C. At this temperature, the water will begin to change from the liquid state to the gas state. For this change to take place, additional energy is required. In fact, every gram of liquid water requires 540 calories of heat energy to convert it to steam. This is called the heat of vaporization or talent heat of steam. So while they both would exist at the same temperature, the steam would have a lot more heat energy due to the addition of 540 calories per gram of heat energy that has been absorbed. This is why steam burns are worse than water burns.

  • The normal core body temperature of a healthy, resting adult human being is stated to be at 98.6 degrees Fahrenheit or 37.0 degrees Celsius. Though the body temperature measured on an individual can vary, a healthy body can maintain a fairly consisted body temperature that is around the mark of 37.0 degree Celsius. If we convert 37 degree Celsius to Kelvin, it equal to 310 Kelvin.

  • The formula to convert Fahrenheit (F0) to Celsius (C0) is –

0 C = (0 F-32)´ 5/9

  • Ethylene glycol is an organic molecule most widely used as antifreeze in automobile engines and as an industrial solvent. When is it mixed with water, the freezing point of the mixture is depressed, specifically a mixture of 60% ethylene glycol and 40% water freezes at – 450 That is why water is not frozen in the engine of cold countries.

  • Absolute zero is the lowest possible temperature at which point the atoms of a substance transmit no thermal energy. They are completely at rest. It is 0 degrees on the Kelvin scale, which translate to -273.15 degrees on the Kelvin scale, which translate to -273.15 degree Celsius.

  • There are lots of reasons for using alcohol than mercury as thermometric liquids. Some alcohol has a very low freezing point of about – 1120 C and therefore is suitable to record very low temperature.

  • Convection is a mode of heat transfer by actual motion of matter. It is possible only in fluids and gases. Convection can be natural and forced.

  • Elements such as cast iron, ice, antimony, bismuth and brass when melts, their volume decreases. These type of solids floats in their own melted fluid.

  • Thermostat is a device which automatically regulates temperature or provides a signal used by another device to regulate temperature.

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  • Refrigerator temperatures do not destroy pathogenic or spoilage microorganisms. The lower temperature slows the growth of microorganisms already in the food. Some bacteria grow most rapidly in the range of temperature between 40 and 1400, the “Danger Zone”. Thus it is necessary to make sure that the refrigerator is maintaining the recommended temperature of 35 to 40 degree F or below. According to international standards, the recommended temperature of the refrigerator is 360 F to 380 F (1.70 C to 3.30 C).

  • If the door of a refrigerator kept open in a room, the temperature will start to rise inside the refrigerator. The thermostat will kick in and try to cool it back down. This means the motor is running which means heat is being added to the room resulting warmer room.

  • If a hydrogen-inflated polythene balloon is related from the surface of the Earth, then the air pressure at high altitude is reduced. Thus the balloon will expand until the pressure inside the balloon equals the pressure outside.

  • Humidity is the percentage of water vapour presented in air. As the humidity increases, the percentage of water vapour in air increase and this decreases the density of air. This results in the increase of velocity of sound. So increase in the humidity of air increases the velocity of sound in air.

  • It is well known that even after harvesting of the fruits the process of respiration continues and brings about ripening, change in colour, softening of flesh, increase in sugar content and development of flavour. These changes occur more rapidly at higher temperature. This means that the lower the temperature of storage the longer would be the storage life of the fruit. In cold storages the rate of respiration of fruits is decreased.

  • Woolen clothes keep us warm in winter. It is just because woolen clothes have fibres and between those fibres, air is trapped which reduces heal loss. Air reduces heat loss because it is an insulator or poor conductor of heat.

  • The cloudy nights are warmer than clear nights because the clouds prevent radiation of heat from the ground and the air.

  • A glass bottle containing water breaks when kept in a freezer because the frozen will have more volume than the liquid water.

  • Steam at 1000 C contains 536 calories more than the boiling water at the same temperature due to the latent heat of vaporization. The latent heat of fusion of ice is 80 cal/gm

  • If the temperature of water is lowered from 90 C to 40 C, then density is maximum at 40 Density is inversely proportional to volume, therefore till 40 C density increases which result in decrease in volumes and later (40 C to 30 C) during the process of ice forming, reduction in density would cause an increases in volume.

  • The maximum temperature inside pressure cooker depends on the area of the hole on the top and weight that is kept on it.

  • Handle of pressure cookers is made up of Abonite because it is an insulator and prevents heat from reaching the handle and prevents burning of hands. Abonite is a strong material.

  • The atmospheric pressure decreases as one climbs higher in the atmosphere and increases closer to the earth’s surface. The boiling point of water decreases as the altitude increases.

  • Food can be cooked faster in a pressure cooker since the boiling point of water increases with pressure. As the water boils, the steam produced cannot evaporate so the pressure inside the cooker increases. The boiling point of water now becomes 1200 The load pin fixed on the heavy aluminium lid prevents any escape of steam. The rubber ring around the lid deals the liquid inside. Thus food gets cooked faster in a pressure cooker.

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  • Xeric condition refers to low humidity. It is a challenging place with poor sandy soil, the extreme condition of rain and drought. Xeric environment is a place where water is meager.

  • The temperature dependence of liquid (Glycerin) viscosity is the phenomenon by which liquid viscosity tends to decrease as its temperature increases. The increase in temperature causes the kinetic or thermal energy to increase and the molecules become more movable.

  • In the season of summer, when the weather is humid, we experience humid heat.

  • The atmosphere exerts enormous pressure on us but we do not feel it, because our blood exerts pressure slightly more than that of the atmosphere. We feel this pressure in water because the pressure under water is greater than our normal blood pressure.

  • Perspiration is often related to heat. When there is a rise in temperature of the surroundings the body heats up and that can be dangerous. The temperature of the body has to be stable or else the cells will start to burst. The problem will occur with the running of the organs and even heat stokes can arise which can lead to death. It is the process of perspiration that cools the body down. The sweat released onto the body cools it down and when the watery substance evaporates from the skin, it takes the heat with it giving a cooling effect.

  • In summer, a ceiling fan in the counterclockwise direction can help to cool your home by pushing cool air down. During the hot summer months, though this wind chill effect can work to your advantage by providing a breeze that can help evaporate the skin’s moisture quickly, creating a cool feeling.

  • White and light colored clothes are poor absorbers of heat, that is why such clothes are preferred in summer.

  • The water remains cold in an earthen pitcher because of a physical process is known as evaporation, when liquid changes to a gaseous (or vapour) state without boiling, it is known as evaporation. The earthen pitcher is made of mud and has many minute pores. It is through these pores that the water, placed inside the pitcher, oozes out. Now to evaporate, the water needs to absorb heat, which will change it to vapour. The only way the water oozing out of the pitchers can turn to vapour is by absorbing heat form the liquid within the pot. Due to this process of continuous absorption of heat from water inside the pot, in a few hours, this water becomes cool.

  • Lightning can even burn a tree because it contains tremendous amount of electrical energy. Lightning is an electrical discharge caused by imbalance between storm clouds and the ground, or within the clouds themselves.

  • If salt is added to water then the boiling point of water will increase. This happens as the boiling point is the temperature at which the vapour pressure of solvent becomes equal to the external atmospheric pressure. Similarly it also decreases the freezing point, which in turn will interfere with the frozen solution’s crystal structure.  That means the temperature will have to the colder to overcome it and freeze the mixture anyway.

  • The glass or steel which is used in thermos bottle is coated with a silver layer to keep drinks at the same temperature for some time.

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  • The wet clothes will dry earliest at minimum humidity & maximum temperature.

  • Most of the air conditioner uses compressed gas, which can cool the room or other places.

  • Most of the modern frost free refrigerator’s uses Dehumidification process in which the moisture or water vapour or the humidity is removed from the air by keeping its dry bulb (DB) temperature constant. As water vapour or moisture condenses, it drips down into a drain, which removes water to the bottom of the refrigerator. This is the main reason for soggy biscuits turns into crisp in the refrigerator. Ice collets in the freezer is the result of vapour and moisture which is expelled by the food and ice tray. It adversely affects the cooling of the refrigerator, as ice is a poor conductor.

  • Heat transmits from hot body to cold body. Ice takes latent heat from the drink to melt and makes drink cooler.

  • A black hole is an object which is so compact that its gravitational force is strong enough to prevent light or anything else from escaping. By this reason, one can’t see it by telescope.

  • Most solids expand when heated and contract when cooled. The rate at which solids expand when heated depends on the substance. Metals tend to have higher rates of expansion than non-metal solids. When a metal ring is heated, there is an increase in outer diameter along with inner diameter. Thus, the ball can pass easily through it.

  • Space-based solar power (SBSP) is a system for the collection of solar power in space for use on earth. SBSP would differ from current solar collection methods in such a way that the means used to collect energy would reside on an orbiting satellite instead of the earth surface. The power is then transmitted via electromagnetic waves at 2.45 GHz to dedicated receiver stations on earth. “Rectenna” which convert the energy back into electricity used in the local grid. The supply of SBSP will be 99% uninterrupted throughout the year besides the enormity. Former president Dr. APJ Abdul Kalam suggested that the space-based solar power (SBSP) should be made a national goal.

  • When a glass rod is placed is steam its length, and width both will increase.

  • Copper is a very good conductor of heat. So it allows the maximum amount of heat to pass through it from one point to other. But glass is a poor conductor of heat and hence it allows a very little amount of heat to pass through it. The density of copper is 8920-8960 kg/m3 and similarly, the density of glass is equal to 24-2800 kg/m3. Thus the density of copper is more than that of glass.

  • Air conditioner and Air Cooler both maintains temperature and the motion of air. But the Air conditioner also having the ability to maintain humidity, while air cooler doesn’t have the ability to maintain humidity.

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Wave Motion

  • The ionosphere is a region of earth’s upper atmosphere from about 65 km to 400 km altitude. It is ionized by solar radiation. It has practical importance because among other functions, it influences radio propagation to distant places on earth.

  • Wavelength means the distance measured in the direction of a wave from any given point to the next point in the same phase, as form crest to crest. The distance between two successive crests or two successive troughs is the wavelength for a transverse wave.

  • Sound waves cannot be transmitted through vacuum. It is transmitted by the movement of particles along with the direction of the motion of the sound wave. More generally, sound is a mechanical disturbance which is dependent upon a medium to travel. It can be transmitted through solid, liquid, and gases.

  • Cosmic rays are not the part of electromagnetic spectrum. They are immensely high-energy radiation waves, mainly originating outside the solar system.

  • Crystallography is the science that examine crystals which can be found everywhere in nature, from salt to snowflakes to gemstones. Crystallographers use the properties of the inner structure of crystals to determine the arrangement of atoms and generate knowledge which is used by chemist, physicists and other. Crystallographers use X-ray, neutron, and election diffraction techniques to identify the characteristic of solid materials.

  • Sound waves are characterized by the motion particle in the medium and are called mechanical waves while Radio-waves, X-rays and light waves are electromagnetic waves.

  • Infrared waves are the type of electromagnetic radiations with longer wavelength compared to those of visible light. It is used in night vision equipment when there is insufficient visible light to see. It is used by the soldiers to find the target, intruders and hidden bombs thus making the application of force more discriminating.

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  • The microwaves are high-frequency signals in the 300 MHz to 300 GHz range. The signals can carry thousands of channels at the same time, making it a very versatile communication system. Microwave is often used for point-to-point telecommunications. Today microwave is employed by telecommunication industry in the form of both terrestrial relays and satellite communication.

  • Ultraviolet radiations are mainly divided into three groups:-

  1. UV-A radiation: The long wave UV-A radiations having the wavelength of 320-400 nm. They strike the surface of the earth as the part of the rays of the sun.

  2. UV-B radiations: The medium wave UV-B radiation has the wavelength of 280-320 nm. It is mostly absorbed by the ozone layer, but some do reach the earth’s surface.

  3. UV-C radiations- it has a wavelength of 100-280 nm. It is completely absorbed by ozone layer and atmosphere. Therefore, on depletion of ozone in the stratosphere, the wavelength radiation striking the surface of the earth will be 100 nm.

  • Radar is an object-detection system which uses radio waves to determine the range, angle or velocity of objects. It is used to detect the location of aircraft, ships, spacecraft, motor vehicle etc.

  • FM broadcasting service uses the range of frequency bands between 88 to 108 MHz. There is a number of bank allocation used around the globe:

  1. 5-108 MHz:- It is the “standard” VHF FM band. The one which is most widely used around the globe.

  2. 76-90 MHz- This VHF FM band is used in Japan.

  3. 8-74.0 MHz- This VHF FM band is known as the ORIT band. It was used in Eastern Europe although few other counties such as Russia, Ukraine also use it.

  • CT Scan or computed tomography are special x-rays tests that produce cross-sectional images of the body using x-rays and a computer.

  • X-rays are a form of electromagnetic radiations, which are used in the diagnosis of intestinal diseases.

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Sound

  • The speed of sound is different for different type of mediums. The speed of sound is maximum in solids while minimum in gases. The speed of sound in air at normal temperature and pressure is 332 m/s. The speed of sound depends on the density of the medium through which it is travelling. The medium which has higher density, the sound will travel faster in that medium.

  • As we know that the speed of sound is different for different types of medium. In general, sound travels faster in liquid than gases and faster in solid than in liquid.

  • The speed of sound depends of the elasticity and density of the medium through which it is travelling. Greater the elasticity and lower the density, sound travels faster in that medium. At temperature of 200 C, the speed of sound is maximum in iron.

  • Sound waves need to travel through a medium such as a solid, liquid or gas. The sound waves travel through each of these mediums by vibrating the molecules in the matter. The molecules in solids are packed very tightly but in liquids are not packed as tightly as solid, and in gases they are very loosely packed. The spacing of the molecules, enables sound to travel much faster through solid than gases. So sound waves can travel in solid, liquid and gaseous medium.

  • Sound is a mechanical wave and needs a material medium like air, water, steel etc. for it propagation. It cannot travel through vacuum. Speed of sound is different in different medium. Speed of sound is maximum in solid than liquid and gas.

  • The walls of the hall built for music concert should absorb sounds. Most of the solid walls reflects the sound. If the walls of concert hall reflect the sound, then audience hear the echo sound. So to avoid this, there is a need to built soft surface walls.

  • The repetition of sound produced due to the reflection from a large surface like wall or mountain is called echo. Consider an observer is producing a sound and it gets reflected by an obstacle. The sound travel towards the observer and the observer hear the sound again. Let d be the distance between the observer and the obstacle, V is the sound velocity and t is the time taken by the sound to and fro motion, then the velocity of the sound is given by

V = 2d/t

  • In order for sound to propagate from one place to another, it requires a medium or a fluid move through. The air on the earth allows sound waves to move from one point to another. However, there is vacuum on surface of moon. Thus, there is no sound on the moon.

  • eLISA (evolved Laser Interferometer space Antenna) is a spectacular plan of setting into space three spacecraft, a mother and two daughter spacecraft, which  will fly in triangular formation,  trailing the earth in its orbit around the sun at a distance of over 50 million km. eLISA is aim to measure gravitational waves in the frequency range from 0.1 MHz to 100 MHz.

  • Sound waves are longitudinal-mechanical wave. Sound waves are divided into three categories that cover different frequency range, Audible waves (20 Htz-20000 Htz), Infrasonic waves (<20 Htz) and Ultrasonic waves (>20000 Htz). Ultrasonic waves are used to destroy insects, clean clothes by removing dust, treat diseases, control automatic doors, detection of aircraft and submarine, determination of depth of sea etc.

  • Sonography or ultrasonography is an important mean of clinical diagnosis. It is a diagnostic imaging technique based on the application of ultrasound. It is widely used in the field of medical science. It is mainly used to provide a variety of information about the health of the mother during pregnancy, and the health and development of embryo or foetus.

  • A flute of long length produces the waves of higher wavelength, thus a flute of smaller length produces waves of higher frequency. Transmission of sound in any medium is only possible by longitudinal waves. Thus, sound travels in rocks, in the form of longitudinal wave. Longitudinal waves are the waves in which the displacement of medium is in the same direction as or the opposite direction to the direction of travel of the wave.

  • In a television broadcast, the picture signals are transmitted by amplitude modulation and audio signals are transmitted by frequency modulation.

  • When T.V. is switched on, audio and video start simultaneously. In old models of television, audio was heard immediately but the video starts as it needs some warm up time. But in modern television, audio synchronize is used to correct this sync error.

  • The electromagnetic spectrum consists of all the different wavelength of electromagnetic radiations such as: Radiowaves>Microwave>Infrared >Visible>Ultraviolet>X-rays>Gamma rays.

  • Infrared waves are used to transmit radio and TV signals but some of them are using radio waves. Infrared is an electromagnetic radiation.

  • Musical sound can differ from each other with respect to the following three characteristic –

  1. Loudness (intensity)

  2. Pitch (shrillness)

  3. Quality (timber)

But quality (timber) is that characteristic of a musical sound which enables us to distinguish between two sounds even if they have the same pitch and loudness.

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  • Source of Sound Intensity (In  decibel)

Whisper                               15-20

 Normal Conversation         30-60

Anger Conversation            70-80

Truck Motorcycle                90-95

Instrument factory               100-110

Orchestra                             110-120

Jet Plane                               140-150

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Electric Current

  • Electricity consumption bill is based on the measurement of kilowatt/hour (kw/h). The kilowatt hour is a unit of energy equal to 1000 watt.

  • A dynamo, which is also known as an electrical generator produces direct current through a commutator. It is basically a device which converts mechanical rotation into electric current according to Faraday’s law.

  • When electrical energy is converted into motion, there is no heat loss.

  • Electric motor is a device which converts electrical energy into mechanical energy. Electric motors involve rotation coils of wire which are driven by the magnetic force exerted by a magnetic field or an electric current.

  • An electric battery is a device consisting of two or more electrochemical cell that converts stored chemical energy into electrical energy. There are different types of batteries but all have three basic components, a positive electrode, negative electrode, and electrolyte.

  • Electronic motors operating al low voltages tend to burn out because they draw more current which is inversely proportional to the voltage.

  • A motor car battery usually has six 2 V cells connected in series, which gives it a steady voltage of about 12 V. The capacity of battery is expressed in ampere-hour. An ampere hour is the total amount of electrical change transferred when a current of one ampere flows for one hour. Therefore the total usable charge stored in a battery can be started in term of ampere hour. The electrolyte used is a 35% solution by weight of Sulphuric acid H2SO4 with 65% of water. The electrodes used in motor car batteries are lead (Pb) and lead dioxide (PbO2).

  • An ordinary light bulb has a rather short life because the –

  1. Filament wire is not uniform

  2. Bulb cannot be evacuated completely

  3. Wires supporting the filament melt at high temperature.

  • Tungsten metal is used as filament in electric bulb. When electric current flows through it, is temperature goes up to 25000 C from 15000 Generally electric bulbs convert only 5% to 10% of electric energy to light.

  • According to Ohm’s law, if there is a potential different (V) across a resister then there is a current (I) flowing through it. Current flows in a circuit as a result of different in potential between two points in the circuit.

  • The nickel-cadmium battery is type of a rechargeable battery using nickel oxide Potassium hydroxide and metallic cadmium as electrodes, while potassium hydroxide is an alkaline electrolyte. It is used in calculator, cordless electronic appliances, transistors, portable power tools, photography equipment, flashlight etc.

  • The Earth’s magnetic is believed to be generated by electric currents in the conductive material of its core, created by convection currents due to heat escaping from the core.

  • Manufacturer of electronic equipment sets a power rating for every equipment which shows the maximum power that can be consumed by the specific device.

  • Rectifier is an electric device that converts alternating current (AC) to direct current (DC).

  • Inverter is an electronic circuit that changes Direct Current (DC) to Alternating Current (AC).

  • The transformer supply alternating current or electric power from power grid to those appliances which use different voltage. Transistor is an electronic device which, with the aid of antenna produces electromagnetic signals/radio waves. Primarily it is used for radio, television and in other communication tools.

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  • An electric generator is a device that converts mechanical energy obtained from an external source into electrical energy as the output. A motor converts electrical energy to mechanical energy. A diesel engine in which heat produced by the compression of air in the cylinder us used to ignite the fuel. Solar (or photovoltaic) cells convert the sun’s energy into electricity.

  • A mobile phone charger works on the simple principle of conversion of AC (alternating current) to DC (direct current). As we connect charger to 220 V AC switchboard, the first job of the charger is to step down the high 220 V in 9 v or 10v. A step down transformer is used in mobile phone charger.

  • Starter in the lights increases the current and send it to the choke. Choke oil step up the voltage of the transmitted current and send it back to tube resulting tube light to glow. After this work of the starter gets finished and choke if used to step up and step down the voltage thus prevent the tube light from any damage.

  • F.L. is short form of Compact Fluorescent Lamp. CFL uses significantly less energy than traditional light bulbs (75% less).

  • The normal tube lights are filled with mercury vapour with argon. An electric current in the gas excites mercury vapour which produces short wave ultraviolet light that causes phosphor coating inside the bulb to glow.

  • In Light Emitting Diode (LED) Lamps, gallium arsenide is used as main light emission component which converts electric energy into light. Its life span is greater than that of CFL because LED lamps consumes less energy than EFL.

  • Fuse is a piece of wire of material with high resistance and very low melting point. When a high current flows through the circuit, it gets heated and melts.

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Conductivity

  • In electromagnetism, permeability is property of a material that describes the ability of a material to support the formation of a magnetic field with itself or we can say that it is the degree of magnetization that a material obtains in response to an applied magnetic field it is represented by Greek letter m (Mu). The permeability m of the super conductor is zero.

  • Germanium a brittle silvery white semi-metallic element is typically obtained from smelting zinc or as by-product of burning coal (Jhama). This element if used in transistors.

  • Copper roads are preferred because –

  1. Copper is a better conductor than iron.

  2. Copper is not easily oxidized in the presence of oxygen and water molecules while iron rusted.

  3. Loss of energy is much less with a copper rod than with iron rod, as copper is a bad conductor of heat than iron.

  • Transistors, diodes and integrated circuits can all be classified as semiconductors because they are made from semiconductor materials. Silicon and Germanium being the most common. An early type of transistor and diode were made of Germanium, but silicon is used today for the vast majority of devices.

  • In solid state electronics, either pure silicon or germanium may be used the intrinsic semiconductor which forms the starting point for fabrication. Each has four valence electrons but germanium at a given temperature has more free electrons and higher conductivity. Silicon is by far the more widely used semiconductor for electronics because it can be used at much higher temperature than Germanium.

  • The electrical conductivity of a semiconductor at absolute zero temperature is zero and they behave like an insulator. At this temperature the electric resistivity becomes infinite.

  • In this universe, all the visible things are made up of matter and molecule. The mass is that physical property of the particle which gives them solid structural form. The study of this field is important to know that why some fundamental particles have mass. So the discovering of Higgs boson particles it’s really important to understand this fact.

  • The minerals (Germanium, Silicon) whose electrical conductivity varies between conductors and dielectric are called semiconductors. At absolute zero temperature, a semiconductor behaves like a perfect dielectric.

  • Ceramic oxide plays a vital role in the field research and discovery towards super conductivity. Ceramic super conductive materials are containing Thelium (Ti), Barium (Ba), Calcium (Ca) and Copper oxide (CO). It was discovered in 1980. These materials already conduct electricity at temperature of around – 2000 C (73 K) without losses and therefore called high temperature superconductors.

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Nuclear Physics

  • In 1935 Meson particles were discovered by Japanese Physicist Hideki Yukara. Positron, the antiparticle or the antimatter counterpart of the electron was discovered by C.D. Anderson and U.F. Hess in 1932. In 1939 Hans Bethe described the nuclear reactions that power the sun and other stars. In synthesis of transuranic elements, Glennn T. Scaborg played an important role instead of Enrico Fermi. The fact is that he attempted to prepare a transuranium element in 1934 in Rome but failed to do so.

  • The two physicists Gunter Nimtz and Alfons Stahlhofen of the University of Koblenz, Germany claimed that had propelled microwave photons faster than the speed of light. This would be the direct violation of a key content of Einstein’s special theory of relativity that states that nothing under any circumstances can exceed the speed of light.

  • Cyclotron is a machine used to accelerate charged particle such as alpha particles, deuteron, proton etc. up to a very high speed.

  • Scintillation counter is an instrument for detecting ionizing radiation by using the excitation effect of incident radiation. Radiation on a scintillator material and detecting the resultant light pulses.

  • The sun produces energy by the nuclear fusion of hydrogen into helium in its core. Since there is a huge amount of hydrogen in the core, these atoms stick together and fuse into helium atom. This energy is then radiated out from the core and moves across the solar system. This is the main source of energy for the sun and stars. Besides that the gravitational contraction in stars is also the source of their energy.

  • Solar (or photovoltaic) cells convert the sun’s energy into electrical energy through photoelectric effect. Photoelectric effect is the ability of matter to emit electrons when a light shines upon it.

  • Technology works on the principle of converting solar energy into heat energy by observing it which can be used for electricity generation.

  • Nuclear reactor, formerly known atomic pile used Uranium 235 or Plutonium 239 as fuel. When this fissile atomic nucleus absorbs a neutron, it may undergo nuclear fission. The heavy nucleus splits into two or more lighter nuclei, releasing kinetic energy, gamma radiation, and free neutrons. To control the speed of neutrons in this reaction D2O (Deutarium), graphite and beryllium oxide are used as the moderation. This whole process is called self-sustainable chain reaction.

  • The draft of Indian Nuclear Doctrine was first prepared by National Security Advisory Board (NSAB) in August, 1999.

  • Pokhran is in the Jaisalmer district of Rajasthan. It is remote location in the Thar Desert region and served as the test site for India’s first underground nuclear weapon detonation.

  • Pokhran-II was the series of five nuclear bomb tests conducted by India under operations “Shakti” at the Indian Army’s Pokhran test range on May 11, 1998. It was the second Indian nuclear test after Pokhran-I

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  • “Smiling Buddha” (MEA designation: Pokhran-I) was the assigned code name of India’s first nuclear weapon explosion on May 18, 1974.

  • With a total capacity of 1400 MW, Tarapur is the largest nuclear power station in India. Kaiga Atomic Power Station has four units. All of the four units are small-sized CANDU plants of 220 MW, therefore total installed capacity is equal to 880 MW. Kudankulam atomic power station has an installed capacity of two 220 MWpressurized water reactor s with heavy water as a moderator (PHWR) therefore total installed capacity is 440 MW. All these nuclear power plants are operated by NPCIL (Nuclear Power Corporation of India Ltd.).

  • Kalpakkam Fast Breeder Reactor uses plutonium carbide (PuC) and natural uranium carbide (UC) as fuel. By this, more than 200 MW of nuclear power would be generated. The fuel is an indigenous mix of 70 percent plutonium carbide and 30 percent uranium carbide. However with a view to rising the reactor’s power, it was decided to go on for a full carbide core of 78 subassemblies. The fuel composition w as 55% PuC+ and 45% UC.

  • Many of the nuclear reactors use graphite as a moderator. Graphite is not as effective as heavy water, but it is cheaper and it also has a low degree of neutron capture like heavy water. This makes it possible to use enriched or natural uranium as fuel. Graphite is somewhat susceptible to corrosion and annealing because the moderator blocks are often located in the hottest part of reactor. Graphite also has a tendency to expand with prolonged Neutron exposure.

  • Heavy water (D2O), also called deuterium oxide that contains a larger than normal amount of the hydrogen isotope deuterium. It is used as the moderator in the reactor to slow down the neutrons produced in the fission to .025 eV so that the chain reaction can be sustained. Some reactors use graphite, Beryllium and light water But heavy water is an excellent moderator as it excellent slowing down power and low absorption cross section for neutrons.

  • The reactor’s design is based on the French reactor Rhapsody, with several modifications. Plutonium-uranium mono-carbide developed indigenously as the driver fuel and went critical on 18th October, 1985.

  • Two, 1000 MW pressurized water reactor (PWR) units based or Russian technology are being erected in phase one of the project. An additional four units are scheduled to be added as per the agreement signed between India and Russia in December 2008.

  • Kaiga station is nuclear power generating station situated at Kaiga near the river Kali in Uttar Pradesh Karwar district of Karnataka. Presently it has four units of 220 MW capacity each working properly and among them, the fourth unit was started on 20 January, 2011.

  • Narora power station is located in the IV Seismic Zone. Kalpakkam is located into the II Seismic Zone. Kaiga and Tarapur are located into the III Seismic Zone.

  • The Heavy Water Board (HWB) at trombay, Mumbai oversees the production of heavy water which is used in nuclear reactors. It has 7 heavy water plants at Tuticorin, Kota, Baroda, Thal, Talcher, Manuguru and Hazira.

  • All the institutions are under the Department of Atomic Energy. Organisations and their headquarters are –

  1. Atomic Minerals directorate for exploration and research- Hyderabad

  2. Heavy Water Board –        Mumbai

  3. Indian Rare Earth Ltd –        Mumbai

  4. Uranium Corporation of India Ltd –     Jadu Guda (Jharkhand)

  • The Harish Chandra Research Institute (HRI) is a premier Institute dedicated to research n mathematics and in theoretical physics. It is located in Allahabad (U.P.) and is funded by Department of Atomic Energy Government of India.

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  • Indira Gandhi Centre for Atomic Research (IGCAR) was established in the year 1971 at Kalpakkam (Tamil Nadu), under the department of Atomic Energy, Government of India. The centre is engaged in broad based multidisciplinary programme of scientific research and advanced engineering directed towards the development of fast breeder reactor technology. The design of 500MW prototype fast breeder reactor (PFBR) is completed and the construction is in progress.

  • Although India’s first nuclear reactors (apsara-1956, cirus-1960) as established at BARC in Trombay. However, they are just only research reactors.

  • U-238 and U-235 (which has 143 neutrons) are the most common isotopes of uranium. Uranium-235 is the isotopes of uranium that is used in nuclear reactors. Natural uranium contains only around 0.7% U-235 and most nuclear reactors require a U-235 concentration of between 3% and 5%. The process of increasing the amount of U-235 is called enrichment.

  • Radioactive elements are elements that have an unstable nucleus. When the nuclei are considered unstable, they radiate alpha, beta and Gamma radiation and is converted into a stable element. This type of radiation is visible for naked eye.

  • Uranium is the first in a long chain of radioactive elements that decay until the stable element lead is formed.

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Computer and Information Technology

  • Charles Babbage was considered to be the father of computing after his invention and concept of the Analytical Engine in 1837. The Analytical Engine contained and Arithmetic Logic Unit (ALU), basic flow control and integrated memory. It was hailed as the general purpose computer concept. Unfortunately because of funding issues, this computer was never built while he was alive.

  • Colossus was the name of a series of computer developed for British code breakers in 1943-1945 to help in the cryptanalysis of the Lorenz Cipher. It was designed by the British engineer Tommy Flowers. Alan Mathison Turing also contributed to its design but the fact was that he was not directly involved in it.

  • 2G is short for “2nd Generation” wireless telephone technology which enables us to send text and picture messages and has internet capabilities.

  • A pen drive or a USAB flash drive is a portable data storage device. Pen drives have replaced the floppy drives of the past and have become the most popular data-storage devices among consumers. It is smaller and handy.

  • A mouse is a hardware input device that was invented by Doughlas Engelbart in 1963. The mouse allows an individual to control a pointer in a graphical user interface (GUI) and manipulate on-screen objects such as icons, files, and folders.

  • The first mouse prototype was invented in 1963 by Dr. Doughlas Engelbart. The originated mouse was made of wood, with two wheels and a bottom. The mouse was first made public in 1968 at the Fall Joint Computer Conference.

  • A double-click is an act of pressing a computer mouse button twice quickly without moving the mouse. We can communicate commands to the computer (CPU) by pressing a button on top of the mouse.

  • USB (Universal Serial Bus) was designed to standardize the connection of computer peripherals (including keyboards, digital cameras, printers, portable media players, disk drives etc.) to personal computers, both to communicate and to supply electric power.

  • The most common input device used by the computer are the keyboard and the mouse. The keyboard allows t he entry of textual information while the mouse allows the selection of a point on the screen by moving a screen cursor to the point and pressing a mouse button.

  • A computer is an electronic device that manipulates information or data. It has the ability to store, analyze, retrieve and process data. The work or data which we stored in it, is totally secure and is done by using passwords. Sometimes our system is attacked or infected by the virus. Some common virusz are – Melissa, Marburg, Terrax, 1069, Trojan etc.

  • Dial-up Service is by far the slowest of all internet connections available. Generally, it gives a speed of up to 56 Kbps. Cable modern uses coaxial lines run by cable companies to offer internet access to their consumers. It can generally gives speed of 512 kbps to as much as 20 Mbps. Dial-up service uses telephone lines to transmit internet date and speed is generally the same as a cable modern. Leased lines are used by a business establishment that needs high-speed reliable internet access 24 hours a day.

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  • The first page of any website is known as a home page. We get information of further pages on respective website from the home page.

  • Generally internet is called “a network of networks because it is a global system of the network o f inter-connected computers”. Here millions of private, public, educational, commercial and government networks are connected with internal protocol suite, TCP/IP.

  • Tree topology is a “hybrid” topology that combines characteristics of linear bus and star topologies. The internet is the best example of largest hybrid topology. Tree topology is a good choice for a large computer network as the tree topology “divides” the whole network into parts, that are more easily manageable.

  • Video conferencing (or video conference) means to conduct a conference between two or more participants at different sites by using computer network to transmit audio and video data. Video conferencing system works muck like a video telephone. Each participant has a video camera, microphone, and speakers mounted on his or her computer.

  • Bluetooth is a wireless technology standard for exchanging data over short distance using short-wavelength UHF radio waves in the ISM band from 2 .4 to 2.485 GHz from fixed and mobile devices and building personal area networks, WI-FI means a local area wireless computer network technology that allows electronic devices to connect with network, mainly using the 2.4 gigahertz UAF and 5 gigahertz SHF ISM radio band.

  • Packet switching is a digital networking communication method that groups all the transmitted data into suitably sized blocks called packets, which are transmitted via a medium. The best known as of packet switching is the internet and most local area network.

  • Ethernet is a network protocol that controls how data is transmitted over LAN. Technically it is referred to as the IEEE 3 protocol.

  • Microsoft Disk Operating System MS-DOS is a non-graphical command line operating system derived from 86-DOS that was created for IBM compatible computers. MS-DOS originally written by Tim Paterson and introduced by Microsoft in August 1981 and was last updated in 1994 when MS-DOS 6.22 was released.

  • Li-Fi technology is a ground-breaking light based communication technology which makes use of light waves instead or radio technology of deliver data. Li-Fi technology will enable when the demand for data usage has outgrown the available supply from existing technology such as 4G LTE and Wi-Fi. Using light to deliver wireless internet will also allow the connectivity in environments that do not currently support Wi-Fi such as aircraft cabins, hospitals and hazardous environments.

  • Nicnet is the largest satellite-based communication network of the world. It links and stores information among different countries in the world through satellite.

  • Talaash is a multimedia portal on the internet and also an optical character recognition which is lead by C-DAC in Devanagari.

  • Software NAYAN was developed by C-DAC to safeguard against cyber attacks and threats of data theft.

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  • A virtual private network (VPN) extends a private network across a public network, such as the internet. It enables a computer or network-enabled device to send and receive data across shared or public networks as if it were directly connected to the private network. Hence, benefiting from functionally, security and management policies of the private network.

  • PARAM a series of the supercomputer was designed and assembled by the Centre of Development of Advanced Computing (C-DAC) , Pune.

  • The Open Systems Interconnection (OSI) reference model has been an essential element of computer network design since its ratification in 1984. The OSI model divides the complex task of computer-to-computer communications, traditionally called internetworking into a series of stages known as layers. The ISO-OSI model consists of seven-layer architecture. The physical layer or layer I is the first (lowest) layer. The data link layer or layer 2 is the second layer and the network layer is 3 layer. So it is clear that data link layer exists between physical and network layer.

  • First indigenously developed Indian Super Computer is named as Param-8000. It was developed by the government-run Centre for Development of Advance Computing (C- DAC) in 1991. All the chips and other elements that were used in the making of PARAM were bought from the open domestic market.

  • Vijay Bhatkar is known as the father of Indian supercomputer. He contributed in developing the first supercomputer of India “Param-8000” in 1991.

  • Computer Division of BARC had started development of supercomputers under the ANUPAM project in 1991, based on parallel processing techniques. The first super computer which was based on this parallel processing technique was “Anupam” 860/ 4 using 4 Intel 860 microprocessor base boards as compute nodes. It was developed by Bhabha Atomic Research Centre for their internal work/usages.

  • Supercomputer “Magic Cube” has been made by China to know the earth’s future and calculate the potential changes to the climate and biological systems. Chinese scientists hope to calculate almost everything in natural earth systems from the formation of clouds to changes in climate in hundreds or thousands of years from now.

  • Word length of a personal computer is 8 bits while for super computer it is 64 bits.

  • Super Computer is fastest, largest and costliest among personal computer, laptop and notebook.

  • Indian Institute of Remote Sensing is situated in Dehradun.

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  • Energy Conversion          Device/Mechanism

Heat to electric                     –        Solar Cell

Electric to sound                  –        Loudspeaker

Mass to heat                         –        Nuclear Reactor

Chemical to heat and light   –        Fuel Combustion

  • Semiconductor laser are solid lasers which are used in laser printers and CD/DVD. It works as a light emitting device. An Excimer laser or Exciplex laser is a form of an ultraviolet laser which is commonly used in the production of microelectronic devices and eye surgery. A gas laser is mainly used to make hologram and also used to read the bar code printed on the various products. The dye laser is mainly used in astronomy and spectroscopy.

  • MICR is an acronym for Magnetic Ink Character Recognition. It refers to the formulation of toner used to print the specialized fond at the bottom of checks and other negotiable documents. It is mostly used in Banking sectors.

  • Nowadays the computers which are mostly used are micro-computers such as desktop computer, game consoles, laptop, notebook tablet computer, smart phones, Palmtop (PDAs) etc. These are types of microcomputers.

  • Desktop publishing or DTP is a modern technique of publishing. It is a wider range of low cost, easy to use software that doesn’t require traditional design and pre-press skill to understand and use.

  • A daisy wheel printer is an early type of impact printer invented in 1969 by David S. Lee at Diablo Data Systems. Impact printers rely on a forcible impact to transfer ink to the media. Dot matrix printers are also categorized as an impact printer.

  • WWW stands for World Wide Web. The inventor of this system was Tim Berners Lee.

  • The World Wide Web is an information system of interlinked hypertext documents and other resources that are accessed via internet. With the help of the web browser, we can visit web pages which contain text, images, video and other multimedia items. Embedded hyperlink permit users to navigate between pages.

  • The Bluetooth technology was firstly developed in 1994 by Hurston. Through this technology mobile phones, laptops, calculators, and digital cameras are connected and share information and data by using radio waves.

  • Cyberspace, Upload and Modem terminology related to information technology but optical storage are related to the computer device.

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  • A backs hat hacker, sometimes called a cracker, is someone who breaks computer security without any authority and uses technology to deliberately damage the system commit fraud, steal identity and other illegal activities.

  • Junk email messages are “spam” messages which are unsolicited (and typically unwanted) email messages that are filtered by the service. By default, the service rejects the spam message based on the reputation of the sending IP address.

  • Spam is flooding the Internet with many copies of the same message in an attempt to force the message on people who would not otherwise choose to receive it. Most spam is commercial advertising often for dubious get rich quick schemes or quasi-legal services.

  • E-mail “bombing” is characterized by abusers, repeatedly sending an identical email message to a particular address.

  • Denial-of-service (or DOS) attacks are usually launched to make a particular service unavailable to someone who is not authorized to use it. These attacks may be launched using one single computer or many computers across the world.

  • Google Chrome is a freeware web browser developed by Google. It was first released in 2008 for Microsoft Windows and later ported to Linux, Macos and Android.

  • A web browser is a software that is used to view articles, images, movies, music and other information available on a world wide web or local server and to use internet facilities, Opera, Vivaldi and Mozilla Firefox are example of web browser where as Google  Apps is not a web browser.

  • WiMAX is short for World Wide Interoperability for Microwave Access. It is a communication technology which helps to transmit data without wire.

  • Computer is of two types –

  1. Analog Computer

  2. Digital Computer

  • Computer languages are expressed in Binary Code.

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  • Computer works in three modes –

  1. Real Mode

  2. Protected Mode

  3. Virtual Real Mode

  • Vidya Vahini project involves taking computer education to primary government schools across the country.

  • World Computer Literacy Day is celebrated on 2nd

  • Michael Angelo was one of the first virus which was designed to infect MS-Dos on 6th March 1992. It was found in Australia in 1991 for the first time.

  • “Flash Memory” which is used in computers and other digital bodies or devices is a type of memory that persists even when the power is off. Pen drive, digital camera, and memory card are the examples of flash memory. In comparison to the hard drive, a flash memory is a much energy efficient. But if we compare in the terms of per unit storage of flash drive, it is expensive than normal hard drive.

  • The full form of UPS is “Uninterrupted Power Supply”. An uninterrupted power supply (UPS) is a device that allows the computer to keep running at least for a short time when the primary power source is off and hence could be properly shut down.

  • The first digital computer built with IC chips is known as IBM system/360. It was a mainframe computer which was developed in 1964.

  • SMPS stands for Switched-Mode-Power-Supply. In a modern computer, there is a SMPS that takes rectified AC input, perform power factor correction and then converts the output into low voltage DC required by the computer.

  • A motherboard is a physical arrangement in a computer that contains the computer’s basic circuitry components. The chipset is the main part of the motherboard. It manages the data flow between processor, memory, and peripherals. The chipset plays a crucial role in determining system performance.

  • FTP is a short form for File Transfer Protocol, the protocol for exchanging files over the Internet.

  • URL stands for uniform resource locator. Every web page has a definite and different address. The address is known as uniform resource locator or in short URL.

  • HTML stands for Hyper Text Markup Language.

  • IBM (International Business Machine) is an American multinational corporation which is related to information technology.

  • The web portal DACNEt is related to e-Agriculture. It is an e-governance project of the Department of Agriculture Cooperation, which is being implemented by the National Informatics Centre for the convenience of agriculture online.

  • Cache memory, also called as CPU memory, it random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM. The Cache has the shortest access time or latency of all the levels of the storage system and the highest bandwidth.

  • Microsoft is a software developing organization. Its headquarters are Washington. It was founded by Bill Gates and Paul Allen 4th April 1975.

  • The Basic Input-Output system in computer resides on the Hard disk.

  • SMS means Short Messaging Service. It is used for exchanging messages by mobile phone.

  • ICT stands for Information Communication Technology. ICT refers to any device or a system that allows the storage, retrieval, manipulation, transmission and receipt of digital information.

  • The full form of SIM is Subscribers Identity Module. It is a small card that contains a mobile network subscriber’s account information. This allows the phone using the card to attach to mobile network. About half the size of a typical stamp, the SIM card is not commonly associated with GSM (Global System for Mobile Communication) and UMTS (Universal Mobile Telecommunication System) handsets.

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  • CPU means “Central Processing Unit” where a computer analyses the received information. The whole functioning of the CPU is divided into four parts –

  1. Fetch

  2. Decode

  3. Execute

  4. Write back or store

  • CAD (Computer-Aided-Design) software is used by architects, engineers, drafters, artists, and others to create precision drawings or technical illustrations. CAD software can be used to create two-dimensional (2D) drawings or three- dimensional (3D) models.

  • IRC stands for Internet Relay Chat. It is an application layer protocol which allows people to communicate with which other in real time in text based environment. It is the form of Internet chat or synchronous conferencing on the real time.

  • “Finger” protocol is used to find out the user’s E-mail address.

  • M.R. is short for Optical Mark Reader. It is a method of entering data into a computer system. Optical Mark Reader reads pencil or pen marks made in pre-defined positions on paper forms as a response to questions or tick list prompts.

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  • The computer provides information after analyzing the input given by the user. If happens in a phased manner –

  1. Input

  2. Processing

  3. Computing

  4. Outputting

  • USB (Universal Serial Bus) is the most popular connection used to connect a computer to devices such as digital cameras, printers, scanners and external hard drives.

  • The .com portion of an organization website is short for commercial. It is a top-level domain (TLD) in the Domain name system of the internet.

  • BASIC is a computer language. It is an acronym for Beginner’s All Purpose Symbolic Instruction Code. FORTRAN IS acronym for Formula Translation. It is a high level computer language. C is also a computer language.

  • The main work of assembler is to convert assembly language into machine language.

  • COBOL – stands for Common Business Oriented Language. It is a computer language developed for professional interest.

  • Oracle is a database software, produced and marketed by Oracle Corporation. Database management system is computer software application that interacts with the user, other applications and the database itself to capture and analyze data.

  • ROM is considered as the permanent memory of computer. Data or information in ROM is not destroyed or erased even after the computer is turned off.

  • Celeron, Pentinum and Core are the series of computer

Space

  • Aryabhatta was the first satellite launched by India. It was named after the great Indian astronomer of the same name. Aryabhatta weighed 360 kg and was launched by the Soviet Union on April 19, 1975 from Kapustin Yar using a Cosmos-3M launch vehicle.

  • INSAT-3C by the Ariane 4 launch vehicle of Arianespace from Kourou, French Guiana in South America. The latest series of INSAT Satellite, IRNSS-1G launched on 28th April, 2016 is the seventh and final satellite in the Indian Regional Navigation Satellite System.

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  • Curiosity – Curiosity is a car-sized robotic rover exploring Gale Crater on Mars as part of NASA’s Mars Science Laboratory mission. It was launched from Cape Canaveral on November 26, 2011.

  • MESSENGER – Messenger was a robotic NASA spacecraft launched in August 2004 to study Mercury’s chemical composition, geology and magnetic field.

  • RUSTAM-I – Rustom is a medium Attitude Long Endurance unmanned combat air vehicle being developed by Defence Research and Development Organized on (DRDO).

  • Aakash-II – The new version of the world’s cheapest tablet.

  • Columbia, Challenger, Discovery, Atlantis operations of all these space shuttles now been closed by NASA. It may be noted that the shuttles may be launched like rockets, revolves around the earth like satellite and again land on the earth like an aircraft.

  • COBE is a satellite dedicated to cosmology. Its goals were to investigate the cosmic microwave background radiation of the universe. Falcon was the largest submarine cable network by Reliance communication. It was inaugurated on September 5th Presently this system connects Indie with four continents and eleven countries.

  • Atlantis was the last and final space shuttle of NASA. It was launched on July 8, 2011 and landed on July 21st, 2011 Columbia space shuttle was disintegrated during re-entry in earth’s atmosphere on February 1st, 2013. The last Mission of Discovery space shuttle was held between February 24th to March 9, 2011. On May 16th, 2011 the Endeavor was launched for its last space mission and it successfully landed on the earth one June 1, 2011.

  • Cassini-Huygens is an unmanned spacecraft sent to the planet Saturn. Messenger was a NASA’s robotic spacecraft which orbited the planet is a continuing American Scientific program that employees tow robotic probes, Voyager I and Voyager 2 to study the outer Solar system.

  • Tim Peake is a European Space Agency (ESA) astronaut of British nationally. He is currently living and working on the International Space Station for Expedition 46/47. Tim has a background as a test pilot and a British Army Air Corps officer.

  • Kalpana-I is the first meteoroligical satellite launched by ISRO on September 12, 2002. Originally it was known as Metsat-I but on February 5, 2003, It was renamed to Kalpana-I by the then Indian Prime Minister Atal Bihar Vajpayee in memory of Kalpana Chawla. It is notable that she perished in the space shuttle Columbia disaster on February 1, 2003.

  • India’s first full meteorological satellite was launched on September 12, 2002. The first time the space vehicle PSLV-C4 has entered into the geosynchronous orbit with having more than 100 kg lead, also known as METSAT-1. METSAT-1 was renamed Kalpana-I to honour the late Indian-born astronaut Kalpana Chawla.

  • Electrically charged particles from space travelling at speed of several hundred km/sec cannot reach the surface of the earth because the earth’s magnetic field diverts them towards its poles. Its example is “Aurora”.

  • When the object moves around the earth with the velocity commensurate with the velocity of the earth such that it maintain a fixed position in relation to some place on the earth, it is called geostatic position. All the geostationary satellite works on the same principle.

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  • Patterson divided the atmosphere into five layers –

  1. Troposphere (0-18 km)

  2. Stratosphere (18-30 km)

  3. Mesosphere (30-80 km)

  4. Thermosphere (80-400 km)

  5. Exosphere (400 km and above)

  • Air in the Exosphere is extremely thin in many ways. It is almost the same as the airless void of outer space and in this, the communication satellite are located.

  • Kepler is a space observatory launched by NASA to discover Earth-like planets orbiting other stars. It was launched in 2009. The initial planned lifetime for this was 3.5 years but in 2012 it was expanded up to 2016.

  • Vigyan Rail is a science exhibition on the wheels organized jointly by Ministry of Railway and the Department of Science and Technology. It was started on December 15, 2003 for depicting India’s achievements in various fields of science and technology. Vigyan Prasar is an autonomous organization under the Department of Science and Technology not under the Ministry of Human Resources and Development.

  • K. Kasturirangan headed the ISRO from 1994 to 2003. During this tenure, India launched INSAT- 3B satellite with the help of Ariane 5G rocket from the Kourou launching Station of French Guiana.

  • Television transmission is an example of simplex communication. Simplex line carries are only one directional information.

  • The first Indian Remote-sensing satellite IRS- IA was launched on March 17, 1988 from Baikanour Cosmodrome, Tyuratam, Russia.

  • INSAT-4A, the first one in INSAT-4 satellites series was successfully launched by ISRO on December 22, 2005 from Kourou, French Guiana by Ariane-5G launch vehicle. The satellite weighed 3080 kg.

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  • SITE – Satellite Instructional Television Experiment project launched in 1975, jointly designed by NASA and ISRO.

  • STEP – Satellite Telecommunication Experiment Project.

  • APPLE – Ariane Passenger Payload Experiment was launched on June 19, 1981 by Ariane launch vehicle from Centre Spatial Guyanais near Kourou in French Guiana.

  • IGMD – Integrated Guided Missile Development Program which was launched by DRDO in 1983.

  • Moon Express is the world’s first private flight plan on go to the moon. Implemented in 2017 this plan was granted by Federal Aviation Administration on August 3, 2016.

  • INSAT-1D was launched on June 12th, 1990. INSAT-1D was a multifunctional satellite that provides telephone, television, and weather observation for India.

  • Satellite launched Time –

SLV          –        August 10, 1979

ASLV        –        March 24, 1987

PSLV        –        September 20, 1993

GSLV        –        April 18, 2011                                                                                                                                                                                                                                                                                                                                                                                                          

 

  • IIRS –        Indian Institute of Remote Sensing, Dehradun (Uttarakhand)

SAC          –        Space Application Centre, Ahmedabad (Gujarat)

NRSA       –       National Remote Sensing Agency, Hyderabad (Andhra Pradesh)

ISRA         –       Indian Space Research Organisation, (Bengaluru,  Karnataka).

 

  • The Master Control Facility (MCF) is a facility set up by the ISRO in Karnataka. It was established in 1982 for monitoring and controlling geostationary and geosynchronous satellites launched by ISRO. Another MCF was established in Bhopal in 2005.

  • Vikram Sarabhai Space Centre is located in Thiruvananthapuram, Kerala. ISRO’s headquarters is located in Bengaluru, Karnataka. IUAC is established in New Delhi IUCA is established in Pune, Maharashtra.

  • The ISRO Satellite Centre was established in 1972 at Bengaluru, Karnataka.

  • The upper surface of the wings of an aeroplane is made convex and built concave at lower surface. Such design of the wings makes the air velocity faster at the upper surface than the lower surface, which creates low pressure at the upper side. This pressure difference provides lift to the wings of the plane.

  • Chandrayan-I, India’s first mission to the moon was launched successfully on October 22, 2008 from Satish Dhawan Space Centre, Sriharikota (Andhra Pradesh) and the vehicle was successfully inserted into lunar  orbit on November 8, 2008. This mission was operational until August 30, 2009.

  • Marking India’s first venture into the interplanetary space, MOM (Mars Orbiter Mission) or Mangalyaan will explore and observe Mars surface features, morphology, mineralogy and the Martian atmosphere. India is the first Asian country and ISRO is the fourth space agency to send a satellite to the Mars.

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  • GSAT-4 was an experimental communication satellite launched by ISRO in April 2010 which failed to reach to orbit after the rocket’s third stage malfunctioned. GSAT5P was the fifth satellite launched in the GSAT series. It was an exclusive communication satellite to further argument the communication services currently provided by the Indian National Satellite system. Weighing 2310 at the lift. GSAT-5P carried 34 Normal C-band and 12 extended C-band transponders. However, GSAT-5P was not placed in orbit as GSLV-F06 could not complete.

  • Bhuvan is a software application developed by ISRO, which allows users to explorer a 2D/3D representation of the surface of the earth. Apart from visualization it also provides disaster support service. It is an Indian version of Google Earth.

  • RISAT-2 or Radar imaging satellite-2 is an Indian Radar reconnaissance satellite that is part of India’s RISAT program. It was successfully launched by PSLV-C 12 rocket on April 20, 2009 from Satish Dhawan Space Centre, Srihairkota. It was designed to monitor India’s border. ANUSAT is an experimental communication satellite designed and developed by Anna University, Chennai. It was successfully launched aboard PSLV- C 12 along with RISAT-2 from the same place.

  • Galileo is Europe’s own global navigation satellite system, providing a highly accurate and guaranteed global positioning service under civilian control. It is Inter-operable with GPS and Glonass and Russian global satellite navigation systems. The fully deployed Galileo system consists of 30 satellites Positional in three circular medium earth orbit planes at 23222 km. altitude above the Earth. The first Satellite of this series, Glove-A was launched on December 28, 2005.

  • The cryogenic engine generally uses cryogenic liquid fuels such as liquid oxygen or liquid hydrogen that require for  storage at an extremely low temperature in order to maintain them in a liquid state. The propellant that is used in GSLV rockets is kept in the liquid state at low temperature with the help of cryogenic engines. Thus, it is clear that the engines based on cryogenic technology use liquid propellant. Cryogenic engines are also used in space shuttles.

  • Thumba Equatorial Rocket Launch Station (TERLS) was established in 1962 at Thiruvanathapuram, Kerala.

  • In Physics, Cryogenics is the study of the production and behaviour of materials at very low temperatures i.e. below- 1500 C (123 k – 2380 F).

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Defence

  • “Nag” is a “Fire and Forget” anti tank missile developed in India. Land based Nag Missile has range of 500 m to 4 km. It’s first successful test was done on November 24, 1990. It uses nitramine-based smokeless extruded double base sustainer propellant.

  • Prithvi –        Surface to surface missile

Trishul     –        Surface to air missile

Pinaka      –        Multi-barrel rocket launcher

Nishant     –        A remote operated battlefield inspection vehicle.

Agni          –        Intermediate range ballistic system

NAG         –        Anti Tank missile

  • Trishul is a short range surface to air missile developed by India as a part of the Integrated Guided Missile Development program. Prithiv and Agni is a tactical surface to surface short range ballistic missile, while Nag is a anti-tank missile.

  • Astra is an active radar homing Beyond-Visual-Range Air-to-Air Missile (BVRAAM) developed by the Defence Research and DRDO. It has the capacity to destroy the enemy plane up to a distance of 80 km. Ballistic flight test of the missile was carried out from the integrated test range at Chandipur on May 20, 2011.

  • In 1980 the Integrated Guided Missile Development Program (IGMDP) was conceived by renowned scientist Dr. APJ Abul Kalam and this program AGNI, an intermediate range surface-to-surface ballistic missile was developed.

  • INFACT-82 is Indian Naval’s Fast Attack Craft which was Inducted in Indian Navy on October 29, 2003. It was built with help of Israel. Some of the virus positively affect the environment and helps to reduce the pollution. Brahmos is a supersonic cruise missile. It is a joint venture between the Russian Federation and India. Typha is a computer virus.

  • Prithvi-II is a single-stage liquid fuelled missile having a maximum warhead mounting capability of 500 kg with a range of 250 km. In November, 2006 DRDO successfully conducted the interception test using a Prithvi-II missile. In this test an exo-atmospheric hypersonic interceptor missile was destroyed an “enemy” Prithvi missile at an altitude of 50 km. Thus the result of this test shows that Prithvi-II is not for guard/protection but an attacking missile. The exo-atmospheric hypersonic interceptor missiles of Prithvi Air Defence (PAD) can be deployed to guard the metros against air attack.

  • India has become the sixth member of the exclusive club to have developed a cryogenic stage in rocketry with America, Russia, European space agency, China, and Japan after successfully testing a full-fledged cryogenic state for 50 seconds at the Liquid Propulsion Systems Centre (LPSC) in Tirunelveli, Tamil Nadu on October, 2006.

  • INS Chakra is an 8140 ton Akula class, a nuclear-powered submarine. It was commissioned on 4th April, 2012.

  • C-130J Super Hercules is world’s most advanced air lifter being used by Indian Air Force. IAF had signed a deal for about 1.1 billion Dollars with the US Military Systems giant Lockheed Martin on January, 2008. The Lockheed Martin Aeronautics is headquartered in Fort Worth, Texas (USA).

  • Operation Pawan was the code name assigned to the operation by the Indian Peace Keeping Force (IPKF) to take control of Jaffina from the Liberation Tigers of Tamil Eelam (LTTE), better known as the Tamil Tigers in late 1987 to enforce the disarmanent of the LTTE as a part of the Indo-Sri Lanka accord. In brutal fighting lasting about three weeks, the IPKF took control of the Jaffina Peninsula from the LTTE at the cost of the Life of 2014 Soldiers.

  • The “New START” is the treaty between the United States of America and the Russia Federation on measures for the further reduction and limitation of strategic offensive arms. It was signed on April 8, 2010 in Parague by former Russian President Dmitry Medvedev and American President Barack Obama. Under the term of the treaty, the number of strategic missile launchers will be reduced by half and it limits the number of deployed strategic nuclear warheads to 1550. It came into force of Feb 5, 2011.

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  • DRDO has deployed an Unmanned Aerial Vehicle (UAV) especially for Anti-terrorist and counter-insurgency operations. The 1.5 kg UAV “Netra”, is a collaborative development project between Idea Forge and Development Oraganisation’s Pune-based labs (R&D). It is able to fly up to a height of 200-300 meters.

  • SLINEX-II is the largest joint fleet exercise between the Indian and Sri Lankan navies, conducted in Trincomalee, Sri Lanka, during September 19 to 24, 2011.

  • Lakshya is the first unmanned aircraft developed by India. It was developed by Aeronautical Development Establishment (ADE) of DRDO.

  • A supersonic cruise missile “Brahmos” is a jointly venture between the Russian Federation’s NPO Mashinostroyenia and DRDO. The name Brahmos is formed from the names of two rivers, the Brahmaputra of India and the Moskva of Russia. It has a speed of 2.8 to 3.0 Mach, with a range of 290 km. The submarine variant of Brahmos was test fired successfully for the first time from a submerged pontoon near Vishakhapatnam at the coast of Bay of Bengal on 20 March, 2013.

  • INS-SHAKTI is the second fleet tanker built by the Italian yard for the Indian Navy. It was launched on October 11, 2010 and commissioned on October 1, 2011. It was built by Fincantieri, an Italian shipbuilding company based in Trieste.

  • “Vishwast” the first of the new class of offshore patrol vessel indigenously designed and built by Goa Shipyard Ltd. was inducted into Indian Coast Guard on March 17, 2010. Another offshore patrol vessel “Vijit’ was to also commissioned on December 11, 2010 in Indian Coast Guard.

  • Indigenously developed Tejas is a 4th generation light combat aircraft. It was named by former Prime Minister Atal Bihari Vajpayee. This plane was handed over to Indian Army in 2011.

  • Shaurya missile has a maximum speed of 7.5 Mach & it has a range of 700 km along with 100 kg of payload. It is a short range ballistic missile.

  • Admiral Gorshkov is a Russian Naval aircraft carrier ship. This giant ship of Soviet Union served the Russian Navy from 1987 to 1997. On January 2004, India and Russia signed a $94 7 million deal to refurbish or renovate and convert the Soviet/Russian Amiral Gorshkov into a full carrier, to be renamed INS Vikramaditya. On November 16, 2013 it was inducted into India Navy.

  • Abul Pakir Jainulabdeen Abdul  Kalam was an Indian Scientist and administrator, who also served as the 11th president of India from 2002 to 2007. He played a vital role in the development of Integrated Guided Missile Development Programme (IGMDP) in India, Nag. AGNI, Prithvi, Trishul and Akash missiles are developed under this program. For his significant contribution in this field, he was awarded “Bharat Ratna” in 1997.

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Scientist & Invention

  • In 1718 an Englishman named James Puckle (1667-1724 AD) invented defence gun what proved to be one of the keys steps in the evolution of mechanical machine guns. That year Puckle, a London solicitor patented what he called the Defence Gun. There is some argument among historians about whether this was the first patent of a manually operated revolving-type machine gun, but he importance of Puckle’s gun is that it certainly represents the most refined design to be found till that time.

  • Thermometer or thermoscope was discovered by famous Italian physicist Galileo in 1609.

  • Telescope was invented by Galileo in 1609.

  • The typewriter was invented by Sholes in 1868. X-ray was invented by Wilhelm Roentgen in 1895, Radio was invented by Guglielmo Marconi in 1901. Safety lamp was invented by Humphry Davy in 1815.

  • A microscope is an equipment that helps in watching micro and nearby objects which cannot be seen by naked eyes.

  • The Ice Cube telescope which was built in December, 2010 is the biggest neutrino telescope of the world. It was designed by the University of Wisconsin.

  • British physicist and chemist Sir William Henry Bragg shared a noble prize in physics with his son William Lawrence Bragg in 1915. With help of his son, he developed x-ray spectrometer for the analysis of crystal structure by mean of x-rays.

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  • Scientist Invention

John Guttenberg         Printing Press

W.K. Roentgen           X-ray

Michael Faraday         Dynamo

James Watt                 Steam Engine

Thomas Edison           electric bulb

 Daimler                      Gas engine

Waterman                   Fountain Pen

Robert                         Radar

Dynamite                    Alfred Nobel

J.L. Baird                    Television

Theodore Maiman      Lasers

Alexander Fleming     Penicillin

 

 

  • Scientist Albert Einstein is famous for giving the simple & factual explanation of Photo-electric effect on the basis of Planck’s quantum theory. For this, he was awarded Noble Prize in 1921.

  • Indian American astrophysicist Subrahmanyam chandra Shekhar was best known for rendering the theory of Chandra Sekhar Limit. For this, he used Albert Einstein’s special theory of relativity and the principle of quantum physics.

  • Karl Ritter Von Frisch got Nobel Prize in physiology or medicine in 1973 for his work on the investigation of the sensory perception of the Honey Bee.

  • In 1930, C.V. Raman was the first non-white, Asian and Indian to receive the Noble Prize in Physics for the work on scattering of light and discovery of Raman Effect. Every year 28th February is celebrated as National Science Day. It is because on the same day in 1928 he discovered “Raman Effect”.

  • Homi Jehangir Bhabha was an Indian nuclear physicist. He played significant role in development of nuclear energy programme in India. He is known as the father of Indian nuclear programme.

  • Indian physicist Dr. Raja Ramanna contributed a lot to the development of India’s Atomic Bomb. Under this supervision, the first nuclear test (codename Smiling Buddha) was carried out in 1974. He also served as director of DRDO and as Scientific Advisor to the Defence Minister of India in 2000.

  • The theory of Thermal Ionization of gases was first given by M.N. Saha in series of papers (1920 a, 1920 b, 1921) and widely applied by him and others to explain the spectrum of the sun and furnish a satisfactory physical theory of stellar spectra and their classification.

  • The Nobel Prize in physiology or medicine in 1968 was awarded jointly to Robert W. Holley, Har Gobind Khorana and Marshall W. Nirenberg for their interpretation of the genetic code and function of DNA in protein synthesis.

  • Stephen William Hawking is a world famous British theoretical physicist. He is known for his work regarding black holes and for authoring several popular science books.

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Miscellaneous

  • Quantum Mechanics is the branch of physics that deals with the motion of very small particles.

  • Cybernetics is relevant to study of systems, such as mechanical, physical, biological, cognitive and social systems. Cybernetics is applicable, where action by the system generates some change in its environment and that change is reflected in that system. Norbert Wiener defined Cybernetics in 1948 as “the scientific study of control and communication in the animal and machine”.

  • The Higgs Boson is an elementary particle in the standard model of particle physics. Firstly, its existence was suspected in 1964 but practically it was proved on March 14, 2013. In the “God particle”. The two of six physicists who discovered these particles Peter Higgs and Francois Englert were awarded the Nobel Prize in Physics.

  • Horology is the art or science of measuring time.

  • Tribology is a branch of Mechanical Engineering and Material Science. It includes the study and application of the principles of friction and lubrication.

  • “White Dwarf” is related to astronomy. It is also known as Degenerate Dwarf.

  • The violet waves scattered more than blue waves of light. The main cause of skin appearing blue is the highest scattering power on violet.

  • The full form of LASER is “Light Amplification by Stimulated Emission Radiation”. A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The first LASER was built in 1960 by the Russian scientific N.S. Basov and A.M. Prokhorov. The theoretical base came from C.H. Towres in 1965.

  • The National Chemical Laboratory (CSIR-NCL) Pune was established in 1950 is a constituent laboratory of the Council of Scientific and Industrial Research (CSIR). CSIR-NCL is a science and knowledge-based research, development and consulting organization.

  • Presently “The University of Tokyo Atacama Observatory” is the highest telescope observatory in the world which is located at an altitude of 5640 m in the Atacama Desert of northern Chile.

  • April 12, 1961 astronaut Yuri Gagarin became the first human in space by Vostok-I Russian spacecraft. Astronaut Alan Shepard became the first American in space less than a month later.

  • Invention Scientist

Revolver                     Samuel Colt

Law of Cooling           Law of Newton

Law of Pressure          Pascal

  • Russian astronaut Yuri Gagarin was a first male astronaut in space while Velentina Tereshkova (Russian cosmonaut) became the first women to fly to space, when she launched on the Vostok-6 mission on June 16, 1963. She spent almost three days in space and orbited Earth 48 times.

  • Generally drycells is used in the torch, whose anode is made up of zinc while the cathode is made up of carbon.

  • GIF stands for “Graphical Interchange Format”. It is standard for defining generalized color raster images. It allows high quality, high resolution graphics to be displayed on a variety of graphics hardware and is intended as an exchange and display mechanism for graphics images.

  • The Moon is earth’s only natural satellite. It if fifth largest satellite in our solar system.

  • Takashi Hirose is the author of the book “Nuclear Reactor Time Bomb” which he wrote in 2010.

  • GPS means Global Positioning System, is a space-based navigation system. It was developed by the U.S. Department of defence. It became fully operational on 27th April, 1995.

  • ATM is short for Automated Teller Machine. Basically, the ATM is used to perform bank transactions like withdrawal of money and to view bank statement.

  • Black Hole absorbs all radiations that fall on it due to its high gravity.

  • Nanoparticles are typically made from only a few hundred atoms. These are particles lies within the range of 1 nm to 100 nm.

  • “Nano Plug” refers to a small hearing aid. It is so tiny that it is almost undetectable. Nano plug is comprised of micro-components and a nano-battery. It can be programmed by using software running on a computer, the result of which can be downloaded directly to the device via a cable.

  • In the state of weightlessness or microgravity, the size of candle’s flame will be spherical in shape.

  • The Dabhol Power Company (DPC) was formed to manage Dabhol Power Plant. It was built through the combined effort of Enron, GE and Bechtel. It is located at Dabhol Guhagar Taluka, Ratangiri district (Maharashtra).

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  • “Hydrocarbon Vision 2025” is associated with storage of petroleum products and focus on long-term energy security. Aims to assure energy security by achieving self-reliance through increased indigenous production and investment in equity oil abroad.

  • There are two types of members in the non-proliferation treaty (NPT) – Nuclear weapon state and Non-Nuclear Weapon State. Only five countries (including China) who had fired a nuclear devices before 1970 were given the status of – Nuclear Weapon State. Any other nation who wished to sign the NPT had to do so as a Non-Nuclear Weapon state. India exploded its first nuclear device in 1974. This implies that the only option by which India could sign the NPT is being a Non-Nuclear Weapons State. If signs the NPT as a non-nuclear weapon state, India cannot even keep a minimal nuclear deterrent. Hence India finds it discriminatory.

  • ITER (The Latin word for “The Way”) is a large-scale scientific experiment intended to prove the viability of fusion as an energy source. ITER is currently under construction in the France. In an unprecedented international effort, seven partners –

  1. China

  2. The European Union

  3. India

  4. Japan

  5. Korea

  6. Russia

  7. United States

  • DST – Department of Science and Technology Government of India.

CSIR        – Council of Scientific and Industrial Research.

ICSSR      – Indian Council of Social Science Research

DAE          – Department of Atomic Energy Government of India

  • Radiators are heat exchanges used for cooling internal combustion engines mainly in automobiles but also in piston-engine aircraft, railway locomotives, motorcycles, stationary generating plant or any similar use of such an engine.

  • Ball bearing is used in bicycles, cars etc. to reduce the effective area of contact between the wheel and axle. Due to the reduction of the area of contract, the frictional force is also reduced.

  • An organic light-emitting diode (OLED) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. OLED displays can be fabricated on flexible plastic substrates. Roll –up displays embedded in clothing can be made using OLEDs. Transparent displays are possible using OLEDs.

  • The Australia Group in an informal group of countries (none joined by European Commission) established in 1985 (after the use of chemical weapons by Iraq in 1984) to help member controlled so as not to contribute to the spread of chemical and biological weapons. Now it has 42 members. The Wassenaar Arrangement has been established in order to contribute transparency and greater responsibility in the transfer of conventional arms and dual-use goods and technology.

  • “Fat Man” was the code name for the type of bomb which was dropped on the Japanese city of Nagasaki by the United States of America. Plutonium was used as fissionable material in this bomb. On the other hand “Little Boy” which was dropped on the Japanese city or Hirosima on August 6, 1945 used Uranium as fissionable material.

  • Dakshin Gangotri, the first permanent research station of India was established in Antarctica. I was built up in 1984 and buried in 1990. ‘MAITRI’, India’s second permanent research base in Antarctica was built and finished in 1989. BHARTI, India’s third and newest permanent research base which is situated on a rocky promontory fringing the Prydz Bay between Storms and Broknes Peninsula in the Larsemann Hill area. It was set up on January 11, 2011.

  • The European Organization for Nuclear Research is a European research organization that operates the largest particles physics laboratory in the world. CERN is French acronym of the name of the provisional body was founded in 1952, just 2 years before the organization came into existence, i.e. in 1954. It w as established in a north west suburb of Geneva on the Franco-Swiss border.

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CHEMISTRY

 

 

 

 

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Atomic Structure

  • The constituents of an atom are protons, neutrons and electrons. The protons and neutrons (nucleons) are found in the nucleus of atoms. The nucleus of an atom is surrounded by electrons.

  • The nucleus is a very dense region consisting of protons and neutrons at the centre of an atom. It was discovered in 1911 as a result of Ernest Rutherford’s interpretation of the 1909 Geiger-Marsden gold foil experiment. The proton-neutron model of the nucleus was proposed by Dmitri Ivancnko in 1932.

  • Proton, electron and neutron are part of an atom. These particles are also known as three fundamental particles, but the photon is associated with light energy and also known as energy packet of light.

  • The particles that are smaller than the atoms are called subatomic particles. The three main subatomic particles that form an atom are protons, neutrons and electrons. Deuteron contains a proton and a neutron.

  • Native element is a material that consists of a single type of atom, while a compound consists of two or more types of atoms.

  • An alpha particle is a fast moving particle containing two protons and two neutrons (a Helium nucleus). Alpha particles carry a charge of +2 and strongly interact with matter. Produced during alpha decay, alpha particles can travel only a few inches through the air and can be easily stopped with a sheet of paper.

  • The positron or anti electron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric positive charge and has the same mass as an electron.

  • Helium- (2He4) is a non-radioactive isotope of the element Helium. It is far the abundant of the two naturally occurring isotopes of Helium, making up about 99.99986% particle and consists of two protons and two neutrons.

  • The positron has a positive electric charge and has the same mass as an electron. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons and are the components of atomic nuclei. Neutrinos are subatomic particles produced by the decay of radioactive charge or as F. Reines said, “…..the tiniest quantity of reality ever imagined by human being”. A photon is an elementary particle, the quantum of all forms of electromagnetic radiation including light. It is the force carrier for the electromagnetic force.

  • The Aufbau principle is used to determine the electron configuration of an atom, molecule or ion. The principle postulates a hypothetical process in which an atom is “built up” by progressively adding electrons. As they are added, they assume their most stable condition (election orbitals) with respect to the nucleus and those electrons already there.

  • According to the principle, electrons fill orbitals starting at the lowest available (possible) energy levels before filling higher levels (e.g. 1s before 2s).

  • In atomic physics, the magnetic quantum number is the third set of quantum number (principal quantum number, azimuthal quantum number, magnetic quantum number and the spin quantum number) which describe the unique quantum state of an electron and its orientation. It is designated by the letter “m”. The magnetic quantum number denotes the energy levels available within a subshell.

  • The mass number of an element is the sum of a total number of protons and neutrons inside in its nucleus and represents by Therefore, mass number A = number of proton + number of neutron. Therefore, mass number = 2+2 = 4.

  • Two nuclides are isoneutronic (isotones) if they have the very same neutron number N, but different proton number Z. For example, Boron-1 2 and Carbon-13 nuclei both contain 7 neutrons, and so are Isotones.

  • Radioactivity was discovered in 1896 by the French Scientist Henri Becquerel when he was working with phosphorescent materials.

  • The Geiger-Muller Counter also called a Geiger- Counter, is an instrument used for detection and measurement ionizing radiation. It detects radiation such as Alpha particles, Beta particles and Gamma rays using the ionization produced in a Geiger-Muller tube, which gives its name to the instrument.

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Chemical and Physical Transformation

  • Physical changes affect the form of a chemical substance, but not its chemical composition. This fact contrasts with the concept of chemical change in which the composition of substance changes or one or more substances combines or break up to form new substances. In general a physical change is using physical means. For example, sugar dissolved in water can be recovered by allowing the water to evaporate.

  • Change of water into the vapour is called a physical change.

  • A change which alters the specific properties of a material by bringing about a change in its molecular composition, followed by a change in state, is called a chemical change. Into the way the chemical change is a change in which something is formed. Cooking of vegetables is a chemical change as it brings a change in the proteins, carbohydrates etc. which cannot be reserved.

  • A chemical reaction becomes faster at a higher temperature because at high temperature, the molecules have higher Kinetic Energy. The process of a chemical reaction depends on the concentration, temperature and physical state of molecules and their nature. Normally, higher the temperature of molecules, higher would be the reaction.

  • Hydrolysis is the chemical reaction in which ions of a salt dissolved in water, mutually combines with a water molecule to form an acidic for basic solution and the energy produced in this process is in the form of heat.

  • The boiling point of a liquid is the temperature at which its vapour pressure is equal to the pressure of the gas above it. The normal boiling point of a liquid is the temperature at which its vapour pressure is equal to one atmosphere (760 tor).

  • In order to pasteurize milk, first, the milk is heated up to a longer time and then cooled suddenly within specified time. Pasteurization is a process invented the by French Scientist Louis Pasteur during the nineteenth century. In 1864, Louis Pasteur discovered that heating beer and wine was enough to kill most of the bacteria that caused spoilage and hence, prevented these beverages from turning sour. This was achieved by eliminating pathogenic microbes and lowering microbial numbers to prolong the quality of the beverage.

  • At higher altitudes of a mountain, the atmospheric pressure decreases due to lack of air. Therefore, the boiling water pressure decreases and water boils below 1000 C due to lowering of boiling point. The boiling point of a liquid varies depending upon the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than that of liquid at atmospheric pressure. A liquid at high pressure has a higher boiling point than when that liquid is at atmospheric pressure.

  • Water potential is the potential energy of water per unit volume relative to pure water in reference conditions. It quantifies the tendency of water to move from one are to another due to osmosis, gravity, mechanical pressure or matrix effects such as capillary action (which is caused by surface tension). By the addition of solutes in water, lowers its water potential by which it becomes negatively charged Adding solutes makes the water molecules less concentrated and this reduces the chemical potential of water in the system.

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  • In the process of osmosis, the solvent moves through a semi-permeable membrane into a region of higher solute concentration from lower concentration to equalize the solute concentration on two sides. While in reverse osmosis, the pressure as applied to the solution of higher concentration to push it towards low concentration liquid using semi-preamble membrane. The technique is used to purify the solution by making it free from impurities.

  • Chromatography is a separation technique used to separate the different components is a liquid mixture. The separation is based on differential partitioning between the mobile and stationary phase. Chromatography may be preparative or analytical. The purpose of preparative chromatography is to separate the components of a mixture for more advanced use and thus a form of purification.

  • When some impurities mixed with any liquid, its boiling point increases. On the other hand, the melting point generally gets lowered when ice melts at 00 C mixed with salts (NaCl or KNO3 etc). Its mixture is called freezing-mixture.

  • Solid camphor directly changes into camphor vapour and this process is called sublimation. The sublimation is the process in which some substances upon heating directly changes into vapour form and when cooled again directly turns into solid form.

  • Gradual decay of metals by air or chemical substances is called corrosion. Rusting on iron means brown coating on iron, green coating on copper and black coating on silver. These are an examples of corrosion.

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Inorganic Chemistry

  • In the periodic table of chemical elements, the electron affinity decreases down the group but increases up for the group and form left to right across periods of a periodic table because the electron added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons. An atom gets larger as the number of increases as you go down a certain group in the periodic table of elements. However, the size of an atom will decrease as you move from left to right of a certain period.

  • The ionization energies are dependent upon the atomic radius. Since going from right to left on the periodic table, the atomic radius increase and the ionization energy increases from left to right in the periods and decreases as one moves down a given group.

  • The usual property of oxides of Group III and IV of the periodic table are basic and acidic. These oxides are amphoteric (able to react both as a base and as an acid).

  • The element found the maximum in the soil layer is Oxygen 46.8% followed by Silicon 27.72%, Calcium 3.65% and Carbon 0.6%.

  • Chemically diamond is the purest form of Carbon (crystal structure). Hence, it is a fundamental element. Sand is basically made up of Silicon and Oxygen, Marble is made up of Calcium, Carbon and Oxygen while sugar is mainly the mixture of Carbon, Hydrogen and Oxygen.

  • The most abundant element in the Universe is Hydrogen, which makes up about ¾ of all matter. Helium makes up most of the remaining ¼ (25%). This, it is clear that hydrogen in the most common and abundant element in the Universe. While the most abundant element in the earth’s crust in Oxygen making up 46.6% earth mass.

  • The most abundant element on earth’s surface after Oxygen is Silicon. It was discovered by J.J. Berzelius in 1824. The world “Silicon” was taken the Latin word silex, Silicon chips are used as a semiconductor in computers.

Metals, Minerals, Ores: Properties, Uses

  • Calcium is a dull, grey, solid element with a silver appearance which exists in the solid state. It has a high melting point (1115 K) and boiling point (1757 k). All these features make it related to the metals. The valence electron configuration of Calcium is 2, 8, 8, 2. Hence, it has a tendency to lose two electrons to get a noble gas configuration. Since it can lose electrons, it can be used in ionic bonding and can form ionic compounds. Like other metals, Calcium also reacts vigorously with dilute acids like hydrochloride acid and produce large amounts of heat, forms Calcium Chloride (CacCl2) and Hydrogen gas. All these properties of Calcium prove that it is a metal.

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  • Reactivity series (or Electrochemical Series) of metals –

Potassium          –        K      Most Reactive

Sodium               –        Na

Barium               –        Ba

Calcium             –        Ca

Magnesium        –        Mg

Aluminium         –        Al

Zinc                    –        Zn

Iron                    –        Fe

Nickel                –        Ni

Tin                     –        Sn

Lead                   –        Pb

Hydrogen           –        H

Copper               –        Cu

Mercury             –        Hg

Silver                 –        Ag

Platinum             –        Pt

Gold                   –        Au

 

Metals

Atomic No.

Atomic Weight (amu)

Density (g/cc)

1.    Lithium

3

6.941

`0.534

2.    Mercury

80

200.59

13.534

3.    Osmium

76

190.23

22.61

4.    Aluminium

13

26.982

2.70

 

  • Diamond is the hardest, least compressible and best thermal conductor among all natural materials.

  • Nichrome (NiCr, nickel-chrome, chrome-nickel etc) generally refers to any alloy of Nickel, Chromium and often iron and/or other elements or substances. Nichrome is very ductile material. It has high specific resistivity and minimum temperature coefficient. It also has the ability to operate at high temperature. Nichrome alloys are typically used in resistance wire. They are also used in some dental restorations (fillings) and in other applications.

  • Uranium is the heaviest naturally occurring element with an atomic no. of 92. It is a pure form of silver-coloured heavy metal. Its most common isotope Uranium-238 has a nucleus containing 92 protons and 146 neutrons. It has a density of 18.95 g/cm3.

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  • The material, there discovery and cost per gram in US$ are –

Material                     Discovery (in year)            Cost per gram (in US $)

Tritium                        1934                                     30,000

Rhodium                     1803                                     58

Californium-252         1950                                     27 million

Endohedral                  1985                                     167 million

  • The chemical composition of pearl is 85% Calcium Carbonate, 10-14% Conchiolin and 2-4% of water (CaCo3 and H2O). Conchiolin is a protein.

  • Sodium is kept in kerosene to prevent it from coming in contact with Oxygen and moisture present in the air. If this happens, it will react with the moisture and form Sodium hydroxide. This is a strongly exothermic reaction and a lot of heat is generated.

  • There are 2 types of street light bulbs are used by municipalities. They are sodium vapor mercury vapor bulbs. They mercury vapor bulbs are usually a white ambient light and sodium an orange/yellow light. Compared to LPS (Low-pressure sodium) lamps, high-pressure sodium lamps tend to have a longer life, less lumen per watt efficiency and most importantly a higher colour rendering index.

  • Gold is unaffected in air, water, alkali halogen and all acids except Aqua regia (a mixture of hydrochloric acid and nitric HNO3 in a 3:1). The name Aqua-regia was coined by chemists because of its ability to dissolve gold “the king of metals”. It is a mixture of acids, a fuming yellow or red solution.

  • A Sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light. Low-pressure sodium lamps only give monochromatic yellow light and so inhibit colour vision at night and will not split through water droplets. As sodium-vapor lamps cause less light pollution than mercury-vapor lamps, many cities that have large astronomical observations employ them as a street light.

  • Fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and Argon. Sometimes gases like Xenon, Neon or Krypton can also be used. The pressure inside the lamp is around 0.3% of atmospheric pressure.

  • It is an extension of the older carat (Karat in North American spelling) system of denoting the purity of gold by fractions of 24, such as “18 carat” an alloy with 75% (18 parts per 24) pure gold by mass. Because of the softness of pure ( 24 carat gold, it is usually alloyed with base metals for use in jewellerey, altering its hardness and ductility, melting point, colour and other properties. Alloys with lower carat rating typically 22k, 18k, 14k or 10k contain higher percentages of copper or other base metals or silver or palladium in the alloy.

  • Talc is a mineral which is composed of hydrated Magnesium silicate with formula Mg3, Si4O10 (OH)2. On the Mohs hardness scale, the softest mineral talc is rated and the hardest mineral, the diamond is rated 10. In loose form, talc is the widely used substance known as a baby powder (aka talcum). It occurs as foliated to fibrous masses and in an exceptionally rare crystal form.

  • Limestone is a sedimentary rock composed largely of the minerals Calcite and Aragonite which are different crystals form of Calcium Carbonate (CaCO3). Limestone binds with silica and other impurities to remove them from the iron.

  • A group of gypsum cement, essentially hemihydrated Calcium Sulphate (CaSO4 ½ H2O), a white powder that forms a paste then it is mixed with water and then hardens into a solid used in making a cast, mould and sculpture.

  • Good  conductors of electricity are: Aluminim, Brass, Copper, Iron,  Steel

  • Bad conductors of electricity are: Arcylic, Chinaclay, Glass Mica Paper, Plastic & Wood.

From above we find metals are good conductor of electricity because of the nature of its bonds. Bad conductors of electricity are also bad conductor of heat.  So Mica is a bad conductor of heat and electricity both.

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  • Monazite is an important ore for Thorium, Lanthanum and Cerium India, Madagascar and South Africa have large deposits of monazite sands. The deposits in India are particularly rich in Monazite. Its extensive deposits are found in Southern India.

  • Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and the iron itself is usually found in the form of Magnetite (Fe3O4-72.4$ Fe), hematite (Fe2O3-69.9% Fe).

  • Mercury is the only common metal which is liquid at ordinary temperature. Mercury is sometimes called quicksilver.

  • Mercury is easily the best liquid to use in thermometers, five important reasons are –

  1. It is very reflective, so it’s easy to see and to read accurately.

  2. It doesn’t wet the glasses, so you don’t get an inaccurate reading if the temperature is falling.

  3. It is a metal, so it’s a good conductor of heat.

  4. It expends evenly with the temperature so a linear scale can be used with a high degree of accuracy.

  5. There is a large range of temperature for which it is a liquid.

  • Best conductors of heat and electricity          –        Silver

The highest amount of metal is found                     –        Aluminium

Most flexible and able to increase by bang metal –        Gold

Minimum heat conducting                                       –        Lead

  • The precipitated calcium carbonates (PCC) and ground Calcium carbonates (GCCs) are used for general purpose toothpaste specially dentifrices and other oral care products. Calcium Carbonate is insoluble in water so it can only be used in opaque products, not in clear gels.

  • Bauxite is an ore of Aluminium, which is found in the form of Hydrated Aluminium Oxides. It consists mostly of the minerals Gibbsite Al(OH)3, Boehmite g-AlO(OH) and Diaspore a -AIO(OH) mixed with the two Iron Oxides Goethite and Haematite. The French geologist first discovered Bauxite near the village of les Baux, Southern France.

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  • Industrial Purpose Industry with which associated

Cracking                              Petroleum

Smelting                               Copper

Hydrogenation                     Edible Fats

Vulcanization                       Rubber

  • Diamond is a metastable Allotrope of Carbon where the Caron atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Marble is a metamorphic rock composed mainly of crystalline Calcium Carbonate or Calcium Magnesium Carbonate. The most common component of sand is Silicon dioxide in the form of quartz. The earth’s land masses are made up of rocks and minerals. Ruby masses are made up of rocks and minerals. Ruby is considered as one of the four precious stones together with Sapphire, Emerald and Diamond. In Chemistry, the gemstone is a mixture of Aluminium, Oxygen and Chromium.

  • Water has a defined density (gram per cubic centimeter) while the lightest metals are lighter than water. They are Lithium 0.53 gm/cm3, Potassium 0.862 g/cm3, Sodium 0.971 g/cm3. These are malleable and highly reactive so they are impractical to use as the basis of an alloy with any structural utility.

Alloys

  • Galvanization is the process of applying a protective zinc coating on steel or iron to prevent them from rusting and oxidation.

  • Anodizing is an electrical- chemical process by which the surface of a metal is made durable and rust resistant. In this process, a layer of Aluminium Oxide is deposited on Aluminium.

  • Low density and strength make Aluminium ideal for construction of aircraft, lightweight vehicles and ladders. An alloy of Aluminium called Duralumin is often used instead of pure Aluminium because of its improved properties. Easy shaping and corrosion resistance make Aluminium a good material for drinking cans and roofing materials.

  • Bronze is an alloy made up of Copper and another metal Tin. Composition may vary but most modern bronze is 88% Copper and 12% Tin.

  • An amalgam is a substance formed by the reaction of Mercury with another metal. Almost all metals can form amalgams with Mercury, the notable exception being Iron.

  • German Silver or Nickel Silver is an alloy consisting 50% Copper, 35% Zinc and 15% Nickel. It doesn’t have Silver. Solder of Tin and Lead is known as soft solder. The chemical  name of bleaching powder is calcium hypochlorite Ca(ClO)2 (Hypo) Sodium Thiosulphate is a crystalline white smell-less solid.

  • Brass consists 68-71% Copper and rest is Zinz. Bronze consists 88% Copper and 12% Tin. German silver has almost 50% Copper. Gunmetal consists 85% Copper, 5% Tin, 5% Lead, 5% Zinc.

  • Hydrogen Sulphide is responsible for fading of Brass.

  • Stainless steel becomes non-magnetic by combining the Alloy with Nickel, while extra Carbon is mixed to gain more hardness.

  • Stainless steel is alloy with a minimum of 10.5% Chromium content by mass. The presence of Chromium protests steel from corrosion, rust and make it high-temperature resistance.

  • The amount of Carbon contains in Steel lies between 0.1% to 2%

  • Stainless Steel (stain-free iron) is an alloy whose consistent elements are as follows –

Iron                    –        89.4%
Chromium          –        10.0%

Manganese         –        0.35%

Carbon               –        0.25%

  • Due to rust, the weight of Iron increases as Iron is converted into iron-oxide after chemical reaction with Oxygen, in presence of humidity.

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Non-Metals

Carbon and its Various Forms

  • Diamond is an additional form of Carbon. Its relative density is 3.5. Graphite is a slaty-black coloured smooth and brightly organic matter of relative density 2.25, while coal is a solid organic matter used as fuel. All the three are consist of carbon.

  • Graphite and Diamond both are allotropes of Carbon. Pencil cores are made of Graphite mixed with a clay binder which leaves grey or black marks that can be easily erased.

  • In 1996, Robert F. Curl (America), Sir Herald W. Kroto (Britain) and Richard E. Smalley were awarded the Nobel Prize in Chemistry for the discovery of Fullerenes. It was the allotrope of Carbon in which the molecules of Carbon are full condensed. Its molecular formula is C60. It is named as Fullerenes as the name of the scientist Richard Buckminster Fuller.

  • Water gas is a synthesis gas with the mixture of carbon monoxide (CO) and hydrogen (H2).

  • Selenium is a semiconductor. It conducts some electricity but not as conductors and is used in photocells. Selenium exists in several allotropes that interconvert upon heating and cooling carried out at different temperatures and rates. Element number 34, Selenium was discovered by Swedish chemist Jons Jacob Berzelius in 1817. Selenium is a non-metal and can be compared chemically to its other non-metal counterparts found in group 16.

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  • Dry ice sometimes referred to as solid CO2 or dry snow is the solid form of Carbon dioxide.

  • Graphite is the pure crystalline allotropes of carbon. It is also used as lubricant. In its crystals, the carbon atoms are arranged in regular hexagons in layers. Graphite is soft and lubricant due to the presence of weak Vander walls force between its layers.

  • Graphene is an allotrope of Carbon with the thickness of a molecule which shows a remarkable quality. The two scientists of Manchester University-Andre Geim and Kostya Novoselov discovered it in 2004. The both were awarded “Noble Prize” in 2010 for the discovery of Graphene. They extracted Graphene from a piece of Graphite. Graphene is a bi-dimensional element and due to this quality, controlling electricity is easier in it than a tri-dimensional element. Graphene is not only very thin but also stronger among all the matters. Except for the quality of being the conductor of electricity, it has the quality of copper too. It is almost transparent, despite, being so dense that the smallest gas molecule cannot pass through it. Graphene is used in computer chips, communication devices and touch screens etc.

  • Hard water has high mineral content caused by the dissolved Magnesium Sulphate or Calcium Sulphate. This is due to the permanent hardness of sulphate salts which do not decompose on heating. Diamond is the hardest substance. It cannot be dissolved in liquid or no effect of acid and base on it. By volume, dry air contains 78% of Nitrogen. Vanaspati ghee, a fully or partially hydrogenated vegetable cooking oil is often used as a cheaper substitute for ghee.

  • The carat (ct) is a unit of mass equal to 200 mg and is used for measuring gemstones and pearls.

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  • Coal minerals are divided mainly into four types on the basis of the percentage of Carbon amount –

Peat                    –        50-60%

Lignite               –        25-35%

Bituminous        –        45-85%

Anthracite          –        more than 85%

  • Carbon is capable of forming many allotropes due to its valency. The well-known forms of Carbon included Diamond and Graphite. Coal is a sedimentary organic rock that contains a lot of Carbon between 40% to 90% carbon by weight. Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It does not contain Carbon.

  • Buckminster Fullerene is a spherical fullerene molecule (an allotrope of carbon) whose formula is C60. It has a cage-like fused-ring structure which resembles a football, made of 20 hexagons and 12 pentagons with Carbon atoms at each vertex of each polygon and a bond along each polygon edge.

Hydrogen and its Compounds

  • Hydrogen gas is highly flammable and burns in air at a very wide range of concentrations between 4% to 75% by volume. Hydrogen gas cannot burn in absence of air. But by burning with Oxygen it produces water.

  • Hydrogen is the purest combustion fuel. Water is generated from burning of Hydrogen. While coal, kerosene oil and diesel are known as fossil fuel or carbonic fuel which generates Carbon dioxide and many other harmful gases when it burns.

  • Harold Clayton Urey, an American Chemist discovered heavy water in 1931. He was awarded Noble Prize in Chemistry in 1934 for his discovery.

  • Heavy water (D2O), also called deuterium oxide, water composed of deuterium, a hydrogen isotope with mass double that of ordinary hydrogen and oxygen. Thus, heavy water has a molecular weight of about 18.

  • The pH value of pure water is 7. Pure water is neutral by nature. The solution with a pH less than 7 are said to be acidic solutions with a pH greater than 7 are basic or alkaline.

  • During hydrogenation, the vegetable oils are reacted with hydrogen gas at about 1500 A nickel catalyst is used to speed up the reaction. The double bond is converted to the single bond in the reaction. In this way, the unsaturated fats can be made into the saturated fats.

  • Reverse osmosis (RO) is a water purification technology that uses a semi-permeable membrane to remove larger particles from drinking water. Reverse osmosis can remove many types of molecules and ions from solutions including bacteria and is used in both industrial process and the production of potable pure water.

  • Chlorine is presently an important chemical for water purification (such as in water treatment plants), disinfectants and in bleach. Chlorine is usually (in the form of hypochlorous acid) to kill bacteria and other microbes in drinking water supplies and public swimming pools.

  • Alum (aluminium sulphate) is added to the water to destabilize natural fine particulate matter suspended in water. This process is known as coagulation. The impurities found in water suspensions consists of charged colloids ranging in size from 5 mm to 1 mm and particles greater than 0.5 mm. The addition of alum causes these particles to collide and clump together to form heavy particle which will settle in water.

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  • Desalination is a process that removes minerals from saline water (Also refer to removal of salts and minerals). Seawater desalination has a very effective way of production of potable water for drinking and industries.

  • Water is a good solvent due to its polarity which can easily dissolve into polar compounds. Water dissolves ionic salts by hydrating their component ions. For example, water dissolves NaCl by hydrating and stabling the Na+ and Cl

  • Rainwater gets its compositions largely by dissolving particulate materials in the atmosphere (upper troposphere) when droplets of water nucleate on atmospheric particulates and secondly by dissolving gases from the atmosphere. Its pH value is 7 whereas the water on the earth is mixed with an alkaline material that makes the water impure.

Sulphur, Nitrogen, Halogen, Inert Gases

 

  • The noble gases make a group of chemical elements with similar properties under standard conditions, they are all odourless, colourless, monatomic gases with very low chemical reactivity. The six noble gases that occur naturally are Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe) and the radioactive Radon (Rn).

  • The deep sea divers carry cylinders which contain a mixture of Oxygen and Helium. The presence of Helium generates less airway resistance than air and thereby requires less mechanical energy to ventilate the lungs.

  • Heliox is a breathing gas composed of a mixture of Helium (He) and Oxygen (O2). This is frequently used for respiration by divers in the deep sea. Helium is much less soluble in water than many other gases, such as Nitrogen. The low solubility means it does not enter the blood stream even under pressure.

  • Sulphur hexafluoride (SF6) is an inorganic, colourless, odourless and non-flammable compound. SF6 has an octahedral shape. It has 12 electrons around the central Sulphur atom. This means there are six electron pairs arranged in an octahedral shape.

  • Xenon is a chemical gas with symbol Xe and atomic number 54. It is a rare, odourless, colourless, tasteless, chemically unreactive gas. Xenon is also known as stranger gas as its volume is low in the atmosphere (0.08 parts per million of xenon). It was discovered in England by the Scottish chemist William Ramsay and British chemist Morris Travers in 1898.

  • Ammonia being a polar molecule dissolves readily in water. This is due to the Hydrogen atoms of Ammonia which are bonded with a highly electronegative Nitrogen and the Hydrogen atoms of water molecules which are bonded with the highly electronegative Oxygen atom.

  • Nitrous Oxide (N2O) is also known as laughing gas. It is a colourless gas with a sweet odour and taste. Inhalation leads to disorientation, euphoria, numbness, loss of coordination, dizziness and ultimately a loss of consciousness. It is also used as the anesthetic gas.

  • A gas balloon flies in the air because it is filled with a gas which is lighter than air. Helium is mostly used in gas balloons.

  • Nitrogen gas is used in the types of an aeroplane. This is because the nitrogen gas does not support combustion and can assist in preventing wheel fire when the aircraft lands (braking and high speed can produce dangerously high temperatures) unlike in oxygen. There are other benefits but effectively it is being the lowest cost gas that does not support combustion. It is preferred in comparison with the oxygen because nitrogen does not contain water. Thus, when the plane is at more height, gas in tyres does not frozen.

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  • Helium is preferred over Hydrogen because it is inert in nature. Also, Hydrogen s highly flammable and explosive so it would make it unsafe to use in balloons.

  • Meat-eating or carnivorous plant can trap and digest insects and other small animals. They do this to obtain vital nitrogen that they need to grow. Most of the plants absorb enough nitrogen from nitrates in the soil.

  • Tear gas is a chemical weapon that causes severe eye respiratory and skin burning, plain, vomiting and even blindness. It is mostly used by the police force in controlling nots. Alpha chloro acetophenol and acrolein are used as tear gas. Ammonia (NH3) is also used in tear gases.

  • Insectivorous plants cannot take their nitrogen from soil as they grow in waterlogged swampy soils deficient in nitrogenous compounds. Such plants obtain their nitrogen from small insects. For this work, these plants have evolved special mode of nutritions. Example of insectivorous plants are Nepenthes, Dionea, Drosera, Utricularia etc.

  • Trimethylamine is a tertiary amine that is structurally an amino compound in which every hydrogen atom of ammonia is replaced by a methyl group. The odor (Smell) of dead fishes is due to the presence of these compounds.

  • A fluorescent tube is a low-pressure mercury vapour gas discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapour which produces short-wave ultraviolet light which results in phosphorus coating inside the bulb to glow.

  • Glycine is a non–essential, non-optical amino acid. It is also know as a building block for a protein. Its formula is NH2 CH2 An optically active compound should have at least one carbon atom attached to four different groups. Glycine is not active because the carbon atom is attached to 2 hydrogen atoms, 1amino group and 1 carboxylic group.

  • The group seven (7) elements are also known as the Halogens. They include Fluorine, Chlorine, Bromine and  iodine which all have 7 electrons in there outer shell. Iodine is a bluish-back solid with a metallic lustre, thus it remains in a solid state at normal temperature.

  • A tube light is filled with a gas containing low pressure Mercury vapour, Argon and Neon or Krypton. The pressure side the lamp is around 0.3% of atmospheric pressure.

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Acid, Base and Salt

  • Aqua Regia is an acidic, corrosive and oxidative mixture of three parts concentrated hydrochloric acid (HCl) and one part concentrated nitric acid (HNO3). It is called aqua regia because it is one of the few acid mixtures that can dissolve the “noble” metals: Gold (Au), Platinum (Pt) and Palladium (Pd).

  • The pH scale measures the acidity or basically of a solution. The solution with a pH less than 7 is said to be acidic while the solution with the pH greater than 7 is basic or alkaline. The pure water a pH value 7. The logarithm of the reciprocal of hydrogen ion concentration in gram atoms per litre is measure by pH scale from 0 to 14.

  • When a red litmus paper is immersed in a base or alkaline, the red litmus paper turns blue indicating the given solution as alkaline/base. When a blue litmus paper is immersed in an acid, the litmus paper turns red from blue indicating acid. The solution having pH value less than 7 is acidic and the solution having pH value more than 7 would be basic.

  • In the chemical industry, the Sulphuric acid (H2SO4) is considered as basic chemical. Sulphuric acid is mainly used in petrochemical industries. It is also used for cleaning purposes in the laboratory.

  • The carbon dioxide (CO2) gas dissolved in water can cause water to become acidic. The acidity of water from dissolved CO2 can be reduced by a base such as baking soda (Sodium bicarbonate). When carbon dioxide is dissolved in the water, it forms as carbonic acid (H2CO3) by reacting with water (H2O) and remains in dissolved state at high pressure. So, the soda water becomes acidic in nature.

  • Washing Soda –        Sodium Carbonate

Caustic Soda               –        Sodium Hydroxide

Hypo                           –        Sodium Thiosulphate

Neela thotha                –        Copper Sulphate

Epsom Salt                  –        Magnesium Sulphate

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  • The aqueous solution of Ammonia changes the colour of red litmus into blue. Ammonia produces a white flame when it reaches with hydroelectric acid.

  • Sodium bicarbonate is also known as Baking Soda. The chemical formula of Sodium Biracbonate is NaHCO3.

  • “Viscocity” of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of “Thickness”. For example, Honey has a much higher viscocity than water.

  • High resolution photographic plates having a coating of exceedingly fine-grained photosensitive emulsion with sub microscopic crystals of silver bromide in gelatin.

  • To develop the photographic plate, the plate is kept in the solution of silver bromide until all the silver bromide is dissolved.

  • Then eno salt is dissolved in water, the Carbon dioxide gas is produced which produces gas bubbles.

  • Sodium Thiosulphate is used in photography as a fixer of positive and negative. It is also used in the extraction of Gold and Silver.

  • Calcium Hypochlorite or Calcium Oxychloride is an inorganic compound. It is also known as bleaching powder. It chemical formula is Ca (OCl). It is a white solid, although commercial samples appear yellow. Bleaching powder is used for water treatment and acts as a bleaching agent. It is not highly soluble in water.

Organic Chemistry

  • The organic compounds are a large class of chemical compounds in which one or more atoms of carbon are covalently linked to atoms of other elements, most commonly Hydrogen, Oxygen or Nitrogen.

  • Biologist considers that six elements were primarily responsible for the origin of life on the earth. They are Hydrogen, Oxygen, Carbon, Nitrogen, Phosphorus and Sulphur. The matter within every living earthly creature mainly consists of these chemical compounds. Protein, Neuclic Acid, Carbohydrates, Vitamins, Hormones etc.

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  • The increasing order of atomic weight of Hydrocarbons –

Methane             –        CH4

Ethane                –        C2H6

Propane              –        C3H8

Butane                –        C4H10

  • Butane is a flammable hydrocarbon with the molecular formula C4H10 . It is a natural gas perhaps best known for its use as a fuel cigarette lighters. It is an organic compound known as NGL, a Natural Gas Liquid.

  • The Bhopal disaster or the Bhopal Gas Tragedy was a disaster that resulted from an accident. It is happened at a Union Carbide subsidiary pesticide plant in Bhopal, India. On the night of 2-3 December, 1984 the plant released 42 tonnes of toxic methyl isocyanate (MIC) gas, exposing more than 500000 people to toxic gases.

  • Mustard gas or sulphur mustard is a chemical compound which has been used as a chemical weapon in the First World War. Its chemical name is “Dichlorodiethyl Sulphid”. It is a poisonous gas. It can cause ulcers on the skin.

  • Paddy fields are a major source of atmospheric methane and have been estimated to contribute in the range of 50 to 100 million tonnes of the gas per annum.

  • Benzene is an important organic chemical compound with chemical formula C6H Its molecule is composed of 6 Carbon atoms and 6 Hydrogen atoms. Its chemical structure can be described as a hexagonal ring with alternating double bonds. It has twelve sigma and three pi bonds.

  • A Fullerene is a molecule of carbon in the form of a hollow sphere, ellipsoid, tube an many other shapes.

  • Dry Ice – We can simply say that Dry Ice is solid Carbon dioxide CO2. It is used as a cooling agent.

  • Mustard Gas –        It is used as a strong chemical weapon. This mortally chemical affects skin, leering eye, lungs and DNA which affects the cells most. After 1-6 hours the symptoms seem to be visible.

  • Teflon          –        Its commercial name is Polytetra Fluoroethylene. It has been registered in 1944. It is synthesized fluoropolymer in which fluorine atom is mixed. So Teflon is a fluorine containing the polymer.

  • Fullerene          –        Fullerene is an allotrope the carbon family in which fully carbon atoms are integrated. It is denoted by C60. In 1985, at Rice University the name “Fullerene” was given by St. Richard Buckminster. Fullerene is an Allotrope of Carbon.

  • Keratin –        It is family of fibrous structural proteins. Keratin is the protein that protest epithelial cells from damage or stress that has potential to fill the cell. It is the key structural material making up the outer layer of human skin.

  • Acetylene is also called as Ethyme (C2H2). It is used in welding. Chloroethane is produced by Acetylene which is used as raw material in plastic industry. The mixture of Calcium Carbide and water producers Acetylene.

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  • In gas welding, the mixture of Oxygen and Acetylene are used.

  • The Chemical Ethephon is often used on wheat, office, tobacco, cotton and rice in order to help the plant’s fruit to ripen more quickly.

  • Hydrogenation is a chemical reaction between molecular hydrogen and another compounds or elements, usually in the presence of a catalyst such as Nickel, Palladium or Platinum. The process is commonly employed to reduce or saturate the organic compounds.

  • In villages, we get light gas for cooking from a biogas plant. From electrocardiography we detect the diseases related to the heart. D.D.T. is an insecticide. Nicotine is present in tobacco, which affects the health most.

  • Methane gas is colourless, tasteless and odourless which are found in the marshy area. Further, it is also present in the decomposition of organic matter and gas released by coal. It is used for the manufacture of carbon black. Carbon black is used for making black printing ink etc.

Alcohol

  • Ethyl alcohol becomes poisonous by the addition of Methanol and Pyridine.

  • Methyl alcohol is colourless liquid. In each ratio, it is soluble in water. Its smell is like a pungent, unpleasant and intensive flavour. In each ratio, it is poisonous while in excess. The intake of Methyl alcohol results in madness, blindness and its excess consumption can also cause death.

  • Methyl alcohol (CH3OH) is called as wood spirit. It is obtained by the destructive distillation of wood.

  • Ethyl alcohol is formed by the fermentation of sugar, which is made of glucose and fructose.

  • Wine is an alcoholic beverage, which is prepared by fermentation of different substances. The percentage of alcohol also varies Gin it. Beer, Champagne, Cider, Port and Sherry, Brandy, Rum, Gin etc. are some important types of alcohol. The beer has the lowest amount of alcohol in it and Rum has highest.

Name                 Alcohol              Raw Material

Rum                   45 to 55%           Molasses

Brandy               40 to 50%           Grapes

Whisky               40 to 50%           Rice

Beer                   3 to 6%               Barley

Champagne        10 to 15%           Grapes

Cider                  2 to 6%               Apple

Polymer

  • Polymerization is the process of joining together a large number of small molecules to make a number of very large molecules. The reactants (i.e. the small molecules from which the polymer is constructed) are called monomers and products of the polymerization process are called polymers. Natural rubber is the natural polymer of Isoprene. Isoprene is a colourless liquid made by destructive distillation of petroleum.

  • Wool, silk, leather are the natural polymers.

  • Polythene is produced by the polymerization of Ethylene.

  • Kevlar is a material commonly used to make bulletproof vests. Kevlar is a para-aromatic polyamide (para-aramid) synthetic fibre. It contains lots of inter-chain bonds which makes it extremely strong. The laminated glasses are also widely used for making bulletproof materials.

  • Natural rubber is a polymer of “Isoprene” which is obtained as a latex from rubber trees. Rubber obtained from an artificial source is known as synthetic rubbers. Synthetic rubber Polystyrene, Duprene Rubber, Neoprene Rubber, Thikol Rubber. Polyethylene, Teflon, Dacron are examples of polymers. Polythene is a polymer of polyethylene.

  • Polytetrafluoroethylene (PTFE) is usually known as Teflon. PTFE is a solid fluorocarbon. Its density is 2.2 g/cm3 and its melting point is 3270 This is especially used for making a non-stick surface coating for utensils.

  • The polymer is a long chain molecule made up of many small identical units. Polymers are common in nature. Wood, rubber, cotton, silk, proteins, enzymes and cellulose are all examples of polymers. A wide variety of synthetic polymers has been produced largely from petroleum-based raw materials. These include polyurethane, Teflon, polyethylene, polystyrene and nylon. Caprolactam (CPL) is an organic compound with the formula (CH2)5C (O) NH. It is being used as a raw material for nylon.

  • Zinc Oxide is used in glazing the pottery. Here are some more Oxides which are used in glazing-Silicon dioxide, Aluminium Oxide, Barium Oxide, Sodium Oxide etc.

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Organic Acid

  • Formic acid (HCOOH) and Acetic acid (CH3COOH) both are organic acids. Formic acid is stronger than Acetic acid because it gives out Oxygen easily.

  • Lemon contains citric acid (C6H8O7) which fulfills the deficiency in the body. Due to the lack of vitamin C, one may suffer from Scurvy disease. Citric acid is a weak organic acid found in citrus fruits. Citric acid is most concentrated in lemons and limes, where it can comprise as much as 8% of the dry weight of the fruit. Acetic acid is found in vinegar, while Tartaric acid is found in tamarind.

  • Lactic acid is found in milk, Acetic acid is found in vinegar, Citric acid is found in lemon and Butyric acid is found in rancid butter.

  • Tartaric acid is found in abundant in grapes, tamarind and banana. This acid is used as regular and antioxidant in food items.

  • Ascorbic acid or vitamin C is found in many fresh vegetables and fruits such as cauliflower, lemon, cabbage and citrus fruits. Maltose is found in Malt. Malt is a germinated cereal that has been dried in a processes known as “Malting”. Lactic acid is found in curd. Formic acid occurs in the body of red ants and in the stings of bees.

  • Oxalic acid is used in photography as Ferrous Oxalate. Formic acid is found in ants. Citric acid is found in lemon and Acetic acid is also found in vinegar.

  • Tartaric acid is used in the manufacturing of baking powder. This tartaric acid occurs naturally in many plants particularly in grapes, bananas and tamarinds. It is commonly combined with baking soda to function as a leaving agent in recipes and is one of the main acids found in wine.

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  • Matter Acid

Pickle                          Acetic Acid

Sour Milk                    Lactic Acid

Apple                          Malic Acid

Cold Drinks and Soda water   Carbonic Acid

  • Acetic acid (CH3COOH) or Ethanoic acid is an organic acid, which is responsible for sour taste and the pungent smell of the vinegar. The physical and chemical properties prove that vinegar is a solution of Acetic acid. It is produced from fermentation of Ethanol.

  • Acetic acid is the chief component of vinegar. Vinegar is a liquid consisting mainly of acetic acid (CH3COOH) and water. The acetic acid is produced by the fermentation of ethanol by acetic acid bacteria. It is mainly used as cooking ingredients.

The Explosive Substance

  • Generally Carbon Monoxide, Carbon Dioxide, Methane, Oxygen, Nitrogen and Hydrogen gases etc. are found in mines. When combined with air, they cause an explosion. 5.15% of the amount of methane in air is explosive. In air, 12.5%-74% presence of carbon monoxide is explosive. In air 4-74% carbon and hydrogen mixture may blast.

  • Nitrochloroform is used as anaesthetics before the operation of the patient to make them unconscious.

  • Tri Nitro Glycerin (TNG) also known as Nobel Oil, is an explosive fluid. Chemically, it is an organic nitrate compound.

  • RDX, the abbreviation of this word is Research Department Explosive, is also called cyclonite. It is powerful explosive discovered by Georg Friedrich Henning of Germany and patent in 1898 but not used until World War II when most of the warming powers introduced it.

  • Cordite, blasting gelatin or dynamite is the basic essential constituent in Nitroglycerin, while a highly explosive element is Amatol. It is composed of Ammonium Nitrate and TNT (Tri Nitro Toluene) in varying ratios).

  • Nitroglycerine is a heavy, colourless and oily liquid explosive. It is also known as glyceryl trinitrate (GTN) or 1, 2, 3- trinitroxypropane.

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The Fuel

  • The petroleum products are subject to natural fuel. They are made from the fossils buried within the earth. Coke and tar can be achieved by destructive distillation of coal or wood, while coal gas can be created artificially.

  • The use of natural gas in power generation provides a cleaner alternative to coal and other fossil fuels, reducing carbon and other emissions and resulting in both immediate and long-term benefits for public health and the environment.

  • As the octane number is used to measure the ignition stability of gasoline, the cetane number is used as a quality parameter of diesel. The combustion of diesel without spark is provided by compression. Thus as soon as the diesel fuel is ignited and compressed the cetane number will be higher. This identifies the good quality of diesel.

  • Fossils fuels, including coal, oil and natural gas are currently the world’s primary energy sources. The fossil fuels formed from the organic material over the source of million of years have fuelled the global economy over the past century. Yet the fossil fuels are finite resources they can also irreparably harm the environment.

  • A diesel engine is an internal combustion engine in which ignition in fuel is generated by using heat produced by compressing air in closed place. There is no carbureter in diesel engines for combustion as in petrol engines. In a diesel engine, the air inside a cylinder is compressed to such a level so that the temperature of air reaches 800 F and this temperature works as combustion in diesel engines.

  • The heating value of a fuel is the amount of heat that is obtained after one gram (1gm) of fuel is burnt completely in air on oxygen. Hydrogen has the highest heating value among all fuels. Hydrogen in used as a rocket fuel and in burner producing high temperature. The energy value of hydrogen gas is 150, charcoal 33, natural gas 33-50 and gasoline 50. Hydrogen gas was first artificially produced in the early 16th Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance.

  • Methane is the chief component of biogas or gobar gas which is used for domestic purposes.

  • The Octane number of a fuel is the measure of its antiknock quality when it is used a spark ignition, internal combustion engine as compared to the antiknock quality of ISO-octane. The higher octane number of a fuel means the better antiknocking capacity for that fuel.

  • The absorption of Hydrogen gas by Palladium was first noted by T. Graham in 1866. It is used to power a range of new alternate fuel vehicles.

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  • An antifreeze is an additive, which lower the freezing point of a water-based liquid. An antifreeze mixture is used to achieve freezing-point depression for cold environments and also achieves boiling-point elevation to allow higher coolant temperature.

  • There will be less friction due to radial tyres by which the speed of motor car will increase up. The fuel injection is a method or system for admitting fuel into the internal combustion. By this, the use of fuel will reduce. The catalytic converter with exhaust system will save the car engine from heating which increases its efficiency.

  • Tetraethyl Lead (CH3CH2)4 Pb is the chief antiknock agent for automotive gasoline or petrol. In the hot cylinder of a gasoline engine, the bonds between the Lead atom and the Ethyl groups are broken. Upon combustion, the Lead atom forms Lead Oxide (PbO) which prevents fractions of the fuel mixture from burning too quickly and causing a highly undesirable “engine knock”. It is mixed with petrol to increase its anti-knocking rate.

  • CNG is made by compressed natural gas which is mainly composed of Methane (CH4). It is a mixture of hydrocarbons which is found deep inside Earth and have approx. 80% to 90% of Methane.

  • Gasohol, a gasoline extender made from a mixture of gasoline (90%) and ethanol (10% often obtained by fermenting agricultural crops) or gasoline (97%) and methanol or wood alcohol (3%). Gasohol has higher octane or antiknock properties by which it burns more slowly, coolly and completely.

Food Preservation, Nutrition, Medicine

  • The chemical formula of Sodium Benzoate is NaC7H5O2. It is widely used as food preservative, with E number E211. It is the sodium salt of benzoic acid and exists in this formula when dissolved in water and its melting point is 4100

  • Freon is a common refrigerant used in domestic refrigerator. It is the name of a registered patent for a commercial refrigerant manufactured by Dupont. Freon is mildly toxic but stable halocarbon.

  • Animal charcoal also, known as Bone charcoal is primarily used for filtration and decolourization. Bone charcoal is often used in sugar refining as a decolourising and de-ashing agent.

  • Benzoic acid (C7H6O2) or C6H5COOH is the colourless crystalline solid and simple aromatic carboxylic acid. The name is derived from gas benzoin. It is an organic compound that is present in various products ranging from food to cosmetics.

  • The main components of honey are fructose – 38.2%, glucose- 31.3%, sucrose- 1.3%, maltose- 7.1% and water- 17.2%. Fructose or fruit sugar is a simple ketonic monosaccharide found in many plants.

  • Refrigeration preserves foods by slowing down the growth and reproduction of micro-organisms or we can say that by refrigeration we can reduce the rate of biochemical reactions.

  • Organic food is produced by farmers who emphasize the use of renewable resources and the conservation of soil and water to enhance environmental quality for future generations. The organic food is produced without using most conventional pesticides; fertilizers made with synthetic ingredients or sewage sludge, bioengineering or ionizing radiation.

  • When pasteurized milk is heated to a temperature of 30-400 C or even at room temperature and a small amount of old curd or whey is added to it, the lactobacillus in that curd or whey sample starts to grow. They convert the lactose into lactic acid, which imparts the sour taste to curd.

  • The smaller acid fruits are more suitable for jelly making since they are usually high in pectin content and acid. Guavas have high calcium and phosphorus content. High pectin contents make guava suitable for jelly making.

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  • Eugenol is a colourless or light yellow oil extract from clove oil having chemical formula C10H12O2. It smells like cloves with spicy pungent taste.

  • Milk contains a sugar called lactose. It also contains harmless bacteria called lactobacillus, which uses glucose for energy and creates lactic acid as a by-product. It is the lactic acid which makes the milk sour. The presence of lactic acid or lactate in milk is due to the fermentation of lactose caused mainly by lactic bacteria.

  • Homogenization breaks the fat into small sizes so it no longer separates allowing the sale of non-separating milk at any fat specification. The fat in the milk normally separates from the water and collects at the top. Thus the consistency and texture is homogenized. It is a purely physical process, nothing is added to the milk.

  • Potassium Bromide (KBr) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th It is used as a veterinary drug, as an antiepileptic medication for dogs. It is an odourless, colourless crystals or white granular solid with a pungent bitter saline taste.

  • Aspirin is a salicylate. It works by reducing substances in the body that causes pain, fever and inflammation. It is sometimes used to treat or prevent heart attacks, strokes and chest pain. It is obtained from latex tree.

  • An emulsion is a colloid of two or more immiscible liquids where one liquid contains a dispersion of the other liquids. Milk is an example of an emulsion. It is an example of an oil in water emulsion.

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The Detergents

 

  • Soap is a combination of animal fat or plant oil and caustic soda. When dissolved in water, it breaks dirt away from the surface. The modern soap makers use the fat that has been processed into fatty acids. This eliminates many impurities and it produces water as by-product instead of glycerine. Many vegetable fats including olive oil, palm kernel oil and coconut oil are also used in soap making.

  • Emulsifiers are usually long chain compounds with polar groups for example soap. The soap molecule consists of two parts –

  1. Long hydrocarbon branch (C17H35) which is soluble in fat and

  2. Dissolved polar parts in water (COONa+)

During emulsion, the dipolar alkaline group of soap dissolves oil or grease and the polar group get dissolved in water. When rubbed, the greases are suspended in the water in the form of small droplets and flows smoothly with water.

  • A detergent is different from soap. A detergent is a surfactant or a mixture of surfactants with “cleaning properties in dilute solutions”. The most important ingredients in detergents are chemicals called surfactants. The term detergent by itself refers specifically to laundry detergent or dish detergent as opposed to hand soap or other types of cleaning agents. Detergents are commonly available as a powder or concentrated solutions.

  • By adding Sodium Sulphate to the washing powder, it increase the basically of the powder. The addition of Sodium Silicate into the washing powders turns the powder crystalline so that the powder stays in dry form.

The Fertilizers

  • The fertilizer is a substance added to soil to improve plant growth and yield. Nitrogen, Phosphorus and Potassium (N,P,K) are necessary elements of plants. 1.5 to 3 kg of Phosphorus is obtained from 1 metric ton of an organic manure.

  • Nitrogen is an essential element of plants. For wheat cultivation, the nitrogen fertilizer is most important for its growth and development. The deficiency of Nitrogen is probably the most common nutritional problem affecting the plants.

  • Nitrogen, Phosphorus and Potassium are macro-element of the plants. Nitrogen deficiency causes the yellowing of leaves and retard growth and development of plants. Plants absorb phosphorus as phosphate ions. If favours the healthy root growth by helping translocation of food. Potassium plays an important role in the opening and closing of stomata. Boron is micro-element of plants. Its deficiency causes heart rot of beet and internal cork disease in Apple. Its deficiency affects the formation of root nodules in leguminous plants. Boron is also helpful in developing diseases resistance power in plants.

  • The soil activity causes a reduction in the yields of acid-sensitive crops. The acid soils are readily identified by a soil test showing a how pH value. The soil reaction is alkaline when the pH value is above 7, neutral at 7 and acid below 7. The extensive use of Ammonium Sulphate is not recommended on acid soils because of its greater acidifying properties compared to other nitrogen fertilizers.

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  • Urea or Carbamide is an organic compound with a chemical formula CO (NH2)2 having 47% nitrogen approximately. The urea molecule has two amides (NH2) groups containing nitrogen.

  • The excess use of nitrogenous fertilizers in agriculture can affect environment in various manners in which increment of acidity in the soil, leaching of ground water, eutrophication etc.

  • When urea is applied to soil, it is first hydrolysed (i.e. broken by water) into Ammonical form (NH4+) and then to nitrite (NO2) followed by nitrate (NO3) and formed by the process called nitrification. Most crops are use nitrate as a source of nitrogen. However, if the process of nitrification is too rapid, the nitrogen will escape to the atmosphere and plants will not be able to recover it form urea efficiently.

  • The Diammonium Phosphate (DAP) – is used as a fertilizer. Its formula is (NH4)2HPO4. The average pH in solutions is 7.5-8. The typical formulation if 18-46% (18%N, 46% P2O5, 0% K2O).

  • The green undecomposed material used as manure is called green manure. It is obtained in two ways, by growing green manure crops or by collecting green half (along with twigs) from plants grown in wastelands, field bunds and forest.

  • The greater atomic number containing elements Uranium (at no. 92) in the periodic table are known as transuranium elements (23 as of 1999). All of these elements are unstable and decay radioactivity into other elements.

  • Humus usually refers to the natural decay of material such as leaves in the soil’s top layer. It is a dark organic material that forms in the soil when plant and animal matter decays.

  • The foliar fertilization means applying nutrients to plants leaves or needles. Urea is commonly used for foliar fertilization because of its unchanged, high solubility and its rapid and effective absorption by leaves.

  • Urea Super phosphate and Potassium Nitrate are chemical fertilizers. Sodium Sulphate Na2SO4 is the sodium salt of Sulphuric acid. Sodium Sulphate is not used as a chemical fertilizer.

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Miscellaneous

  • Ozone is made up of three oxygen atom (O3) having a “free radical” of oxygen. It will readily give up one atom of oxygen providing a powerful oxidizing agent which is toxic to most waterborne organisms such as bacteria, mold and yeast spores, viruses or harmful protozoans that for cysts. Ozone is the most powerful and rapid acting oxidizer man can produce and will oxidize all bacteria, mold and yeast spores, organic materials and viruses given sufficient exposure.

  • Allethrin is a pyrethroid synthesized insecticide/pesticide. It is an active chemical to remove mosquitoes.

  • Carbon dioxide gas is used in a fire extinguisher to control small fires, often in emergency situation.

  • Aluminium Sulphate is used to prepare fireproof clothes.

  • Pyrethrum is natural botanical insecticide. It has potent insecticidal activity by targeting the nervous systems of insects which affect the nervous system of mosquitoes and diverge them.

  • Pyrethrins are a class of organic compounds normally derived from Chrysanthemum cinerarifolium, a seed plant that has potent insecticidal activity by targeting the nervous system of insects.

  • Potassium Cyanide (KCN) or Zinc Phosphide is a highly toxic chemical used as a rodenticide- a poison to kill the mouse.

  • Aluminium Phosphide is highly toxic with the chemical formula AIP inorganic compound. It is used as a rodenticide, insecticide and fumigant for stored cereals.

  • Greenhouse Gas Concentrations are as follows:

Carbon dioxide (CO2)          –        99.438%

Methane (CH4)                    –        0.471%

Nitrous Oxide (N2O)           –        0.084%

Chlorofluorocarbons (CFCs)       0.07%

  • The United Nations Framework Convention on Climate Change deals with greenhouse gases emission mitigation. It is known that CO2 falls under greenhouse gases. On 22 April, 2016, 175 countries/organisations including India signed the “Paris Climate Change Agreement” to reduce carbon emission. The participating countries had agreed that the average temperature of 21st century should not be increased for more than 20 C in comparison to the temperature of pre-industrial era.

  • Technology Day –        11 May (Pokhran test 1998)

Photography Day        –        19 August

National Sports Day   –        29 August (Major Dhyanchand)

Nagasaki Day             –        9 August (Nagasaki Japan atom bomb)

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  • 2016 –        International year of Pulses

2017          –        International year of Sustainable Tourism for Development

2011          –        International Year of Forests and chemistry by the United Nations

2015          –        Soils and light-based technologies

  • The Bhopal Gas Tragedy happened on 2-3 December 1984 at night.

  • Hydrogen Sulphide is an inorganic pollutant of air. Some other inorganic pollutants are Carbon monoxide, Sulphur dioxide, Nitrous oxide and Nitrogen dioxide.

  • Since, 1976 the Brazilian Government has made it mandatory to blend ethanol with gasoline and since 2007, the legal blend is around 25% ethanol 75% gasoline.

  • Bisphenol A (BPA) is an organic synthetic compound, which is employed to made certain plastics and epoxy resins. It has been in commercial use since 1957.

  • Sulphur dioxide –        Acid rain

Fluoride pollution       –        Teeth

Methyl isocyanate       –        Bhopal gas tragedy

Ozone depletion          –        Skin cancer

  • Potassium bromide is used in photography.

  • Potassium nitrate is used in gunpowder.

  • Potassium sulphate is used as fertilizer.

  • Monopotassium tartrate is used in the bakery.

  • Coke is added to blast furnace for the production of iron/steel. It functions as fuel to supply heat. Besides supplying the heat, it also acts as a reducing agent.

  • Phenyl is an effective germicide. It is derivative of phenol, that is why it also has germicidal property.

  • Aspartame –        Artificial Sweetener

Freon                  –        Refrigerant

Neoprene            –        Synthetic Rubber

Benadryl            –        Anti-histamine

  • Nickel and Cadmium are mainly used as electrodes in torch-light and electric shavers etc. In this, cathode of nickel hydroxide and anode of cadmium is used. Potassium hydroxide is used as electrolyte in it.

  • Electrolyte substance used in a car battery is Sulphuric acid (H2SO4). It is a strong acid.

  • The matters of a dry cell are there in dry form. A zinc pot is there having full of manganese dioxide, sal ammoniac and carbon. This cell cannot be charged because the chemical reaction in it cannot be reserved.

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  • Smokescreens generally consist of fine particles of Titanium oxides. Titanium dioxide is a naturally occurring oxide of titanium. A smoke screen is a cloud of smoke created to conceal military operations. The titanium tetrachloride smoke is irritant and unpleasant to breathe.

  • A dry cell is a type of electrochemical cell, commonly used in the form of a battery in many electrical appliances, torch, calculator etc. Unlike a wet cell, a dry cell can operate in many orientations without spilling as it contains no free liquid. A common dry cell a zinc-carbon battery, sometimes it is called the dry leclanche cell. Ammonium Chloride is used as the electrolyte. Sometimes Ammonium Chloride is replaced by zinc Chloride for having high energy voltage.

  • Cryogenics is the study and use of materials including biological products at very low temperature. Nitrogen, Hydrogen or Oxygen are liquids used in many cryogenic applications. Another use of cryogenic is cryogenic fuels for rockets with liquid hydrogen as the most widely used in the space shuttle. Liquid oxygen (LOX) is even more widely used as an oxidizer, not as fuel.

  • Edaphic is a nature related to soil. Edaphic’s qualities may characterise the soil itself, including drainage, texture or chemical properties such as pH.

  • White phosphorous is a waxy, transparent solid. It sublimes if exposed to light. The sublimation is the process by which solid changes directly to a gas when heated, without first changing to a liquid. The White phosphorus is phosphorescent. It gives off a beautiful greenish – white glow.

  • Red phosphorus and phosphorus trisulfide is used for manufacturing safety matches. The matchstick’s head is typically composed of the mixture of potassium chlorate, red lead, antimony sulphide and glue. The striking surface or match-boxes is typically composed or red phosphorus, antimony sulphide, powdered glass and glue.

  • In India, first water desalination plant was opened in 2005 at Kavaratti in the Lakshyadweep islands. This LTTD (Low Temperature Thermal Desalination) desalination plant with a capacity of 1 lakh litre per day was developed indigenously by National Institute of Ocean Technology (NIOT).

  • Acetone –        Nail polish  remover

Carbon tetrachloride   –        Fire extinguisher

Hydrogen peroxide     –        Dressing of wounds

Liquid ammonia         –        Refrigerant

  • In spite of the name, dry-cleaning is not completely dry. Fluids are used in the dry-cleaning process. In the early days, garment scourers and dryers found several fluids that could be used as dry-cleaning solvents including camphence, benzene, kerosene and gasoline.

  • Eosin is a Tetrabromofluorescein. Most red inks are dilute solution of the red dye eosin

  • The Red colour is supplied by Sodium Chromate. Its chemical formula is Na2CrO4

  • Titanium is being increasingly used in our modern society. It is light, strong and corrosion-resistant. These properties allow it to be used in the aerospace industry, building industry, sports goods industry and as implants in a number of surgical procedures. Titanium is also called the “metal of future”.

  • Skin Cancer –        Ultraviolet Light

Noise Pollution           –        Decibel

Global Warming         –        Carbon dioxide

Ozone Hole                 –         Chlorofluorocarbon

  • First NASA Goddard Space Flight Center confirmed the presence of Methane in the atmosphere of Mars. In 2014, Mars Express Orbiter and Canada France Telescope at Hawai further confirmed the presence of Methane on Mars.

  • Urine odour is caused by the presence of Ammonia. Urine is an aqueous solution of greater than 95% water. Other constituents include Urea 2%, Sodium 0.4%, Ammonia 0.05%, Phosphate 0.6%, chloride, Potassium, Creatinine and other dissolved ions.

 

 

 

 

 

 

 

 

BIOLOGY

 

 

 

 

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Subdivisions of Biology

  • Zoology is a branch of biology. It deals with the study of both living and extinct animals including their structure, embryology, evolution, classification, habits and distribution. Aristotle is known as “Father of Zoology”.

  • Palaeobotany is the branch of palaeonthology or palaeobilogy dealing with the recovery and identification of plant remains from geological contexts and their use for the biological reconstruction of past environments. In India, Prof. Birbal Sahni is known as Father of Indian Palaeobotany.

  • Viticulture is the science, production and study of grapes. It deals with the series of events that occur in the vineyard.

  • Vermiculture is the process of managing and cultivating earth-worms. Earthworms can help turning organic waste into nutrient-rich soil for your garden.

  • Pedology deals with the study of soil formation, soil morphology, and oil classification.

  • Branch –        Study

Ornithology       –        Study of Bird

Genetics             –        Study of Inheritance

Ecology              –        Study of Environment

Palaeobiology    –        Study of Fossil

Phrenology         –        Study of Human skull

Anthology          –        Study of flowers

Agrostology       –        The study of grasses

Palynology         –        Study of pollen grains and other spores

Ethnology          –        Science dealing with different races of mankind

Ethnography      –        A study of specific culture

Ethology            –        Study of the animal behaviour

Ethics                 –        Study of ethical and psychological duty

Demography      –        Statistical Study of populations including human beings

Virology             –        Study of viruses

 Ichthyology       –        Study of fish

Entomology       –        Scientific study of insects

  Parasitology     –        Study of parasitic organisms

Malacology        –        Study of molluscs

Bionics               –        Study of problem solving by humans, animals and its technical application

Bionomics          –        Statistical study of biological problem

Bionomy            –        Study of laws of life

Biometry            –        Statistical study of biological problem

Apiculture          –        Rearing bees

Horticulture       –        Study of fruit and flower producing plants

Sericulture         –        Rearing silk worm

Floriculture        –        Study of flowers for decoration work

Lexicography     –        Compilation of dictionary

Philology           –        Study of language structure and its history

 Entomology      –        Study of Insects

Iconography       –        Study of Idols/arts etc

Osteology           –        Study of bones

Orology              –        Study of mountains

Serology             –        Study of serum

Geology             –        Study of internal structure of the earth and matter found inside it

Pisciculture        –        Fish hatchery

Gerontology       –        Study of the social, psychological, cognitive and biological aspects of aging

Oncology           –        Branch of medical science that deals in treating people suffering from cancer

Teratology         –        Study of abnormalities of physiological development

Serpentology      –        Study of snakes

Herpetology       –        Study of amphibians

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Evolution of Life

  • The age of the earth about 4.6 million years. This dating is based on evidence from radiometric age dating meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar sample. According to recent proof, the life on earth emerged about 2000000000 years ago.

  • Blue-green algae are the oldest organism on earth. They obtain their emerged through phosynthesis. They are also known as Cyanobacteria. By producing gaseous oxygen as a   by-product of photosynthesis, they pay a greater role in dramatically changing the life forms on earth by stimulating biodirversity.

  • Charles Robert Darwin was an English geologist and best known for his contribution to evolutionary theory. Darwin published his theory of evolution in his book “On the Origin of Species” in 1859. It states that all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual’s ability to complete, survive and reproduce. It is called Darwinian Theory.

  • Theory of mutation –        De Vries

Theory of evolution             –        Darwin

One gene one enzyme hypothesis         –        Beadle and Tatum

Operation concept                                  –        Jacob and Monod

  • French biologist Lamarck is best known for his “Theory of Inheritance of Acquired Characters”, first presented in 1801. He was the first person to explain the theory of evolution to the public. In 1809, this theory was published in his book “Philosphie Zoologique”.

  • According to Darwin’s theory of evolution, natural selection is one of the basic mechanism of evolution along with mutation, migration and genetic drift.

  • Huge De Vries is known for his mutation theory of evolution. According to him, new species are not formed by continuous variations but by the sudden appearance of variations, which he named as mutations. He stated that mutations are heritable and persist in successive generations.

  • Lamarckism (or Lamarckian inheritance) is the idea that an organism can pass one characteristic that it acquired during its lifetime to its offspring (also known as inheritance of acquired character). It is named after Lamarck who incorporated following two ideas into his theory of evolution which are considered to be generally true:

  1. Use and disuse of organs- Individuals lose characteristics which they do not require (or use) and develop characteristics that are useful.

  2. Inheritance of acquired traits – Individuals inherit the traits of their ancestors

In the context of organic evolution as explained by Lamarck, the loss of limbs in snakes in explained by the phenomenon of use and disuse of organs.

  • Cheetah also known as the “hunting leopard” had become extinct after 1951. They were found in large number in Chhattisgarh.

  • Cro-magnon is a common name that has been used to describe the first early modern humans. The earliest known remains of Cro-magnon-like humans are radiocarbon dated to 43000 years before. Cro-magnons were robustly built and powerful. The body was generally heavy and solid with a strong musculature. The face was short and wide. The chin was prominent. The brain capacity was about 1600 cubic centimeters, larger than the average for modern humans. However, recent research suggests that the physical dimensions of so-called “Cro-magnon” are not sufficiently different from modern humans to warrant a separate designation.

  • The Mesozoic Era is the age of the dinosaurs and lasted almost 180 million years from approximately 250 to 65 million years ago. This era includes three well known periods, called the Triassic, Jurassic and Cretaceous periods.

  • Archaeopteryx is a connecting link between reptilia and aves. It is a creature in which we found the character of both reptiles and birds. Archaeopteryx dating from about 150 million years ago during the Jurassic period when many dinosaurs lived. It is one of the oldest-known birds. It is the first bird and modified from

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Taxonomy

  • Biologists scientifically estimated the number of arthropod species. About 10 million accounts for over 80% of all known living animal species. All insects to the group “Insecta” which is a class of phylum Arthropoda. Class Insects represents the largest number of world species.

  • Echinoderm is the common name of given to any member of the Phylum Echinodermata of marine animals. The adults are recognizable by their (usually five-point) radial symmetry and include such well-known animals as starfish, sea urchins; Sand dollars and sea cucumbers. Most animals of phylum Echinodermata are oviparous. Oviparous animals lay eggs, with little or no other embryonic development within the mother.

  • Starfish popularly called sea stars are related to the phylum Echinodermata while true fishes belong to the phylum Chordata. Starfish do not have gills, scales or fins which are basic characteristic of fishes.

  • An Amoeba is type of cell or organism which has the ability to alter its shape, primarily by extending and retracting pseudo-pods. In Amoeba, binary is a type of asexual reproduction practiced by unicellular organisms in which the parent cell divides into two daughter cells.

  • Opium is a substance that is derived from the collecting and drying processes of the milky juice that comes from the seed pods of the poppy plant. The primary component of opium is 12% morphine which is an alkaloid that is often processed chemically to produce illegal drugs such as heroin.

  • Heroin is obtained from the Opium poppy. Opium poppy is the dried latex obtained from the opium poppy. Opium latex contains approximately 12% of the analgesic alkaloid morphine, which is processed chemically to produce heroin and other synthetic opioids for medicinal use and for the illegal drug trade.

  • Lichens are two organisms that grow together as a symbiotic relationship. Lichens are a partnership between fungi and algae.

  • Yeast and mushrooms are a fungus. These are free from achlorophyllous and convection tissues who depend on other for food. Yeast and mushroom are the member of ascomycetes and basidiomycetes family respectively.

  • Lichen is a dual plant made from completely different plants-fungus and algae. But lichen seems as one plant because of their close combination.

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  • The chemical composition of linseed (cotton) is as follows –

Cellulose            –        91.00%

Water                 –        7.85%

Protoplasm                  –        0.55%

Elephatic element       –        0.40%

Mineral salt                 –        0.20%

  • Chinese, American, Indians and Black Africans groups of living beings belong to the same species. Homo sapiens is binomial nomenclature (also known as the scientific name) for the human species.

  • Scientists at the Botanical Survey of India (BSI), have discovered a new species of human from a remote tropical rain forests on the Little Andaman Islands. The species, Musa Indandmanesis, was located about 16 km inside the Krishna-Nalah forest on the Island. The scientist who has made discovery described it as a district global species with unique green flower and fruit bunch lux (axis) thrice the size of a regular banana species. The new species is about 11 meters high, whereas the usual banana species is about three to four meter high. The fruit lux of the new species is about one meter which are thrice the size of the regular species.

  • Fishes use gills to breath and gills can only bring oxygen when moist. Out of water, a fish’s gills dries out and then the fish dies.

  • The botanical name of papaya is “Carica papaya”. It is rich in carotene, which is a precursor of vitamin A. The papain enzyme presented in papaya is helpful in digestion. The yellow colour of papaya is due to present of caricaxznthin.

  • Anthocyanins are the pigment compounds and responsible for red, purple and blue colours in many fruits and vegetables. Lycopene pigment is in red colour like tomato, carotene in carrot and xanthophyll pigment present in beetroot.

  • Insects require oxygen to live and produce carbon dioxide as a waste product just as we do. They do not have lungs nor do they transport oxygen through their circulatory systems. Instead, insects use a series of tubes called a tracheal system to perform oxygen exchange throughout the body.

  • Archaebacteria sub-kingdom of the kingdom Prokaryote, which on the basis of both RNA and DNA composition and biochemistry differs significantly from other bacteria. They are thought to resemble ancient bacteria that first arose in extreme environments such as sulphur-rich deep-sea vents. Archaebacteria have unique protein-like cell walls and cell membrane simple organic compounds such as methanol and acetate as food, combining them with carbon dioxide and hydrogen gas from the air and releasing methane as a by-product.

  • Hydrophytes or an aquatic plants are plants, that have adapted to live in an aquatic environment (salt water or fresh water). They are also referred as macrophytes.

  • Trophic level-I includes all autotrophs which synthesize their food by themselves. All green plants belong to this trophic level. Organisms of trophic level-I usually utilize the radiant energy of the sun to synthesize their organic molecules.

  • The maximum amount of water is absorbed by root hairs. These are outermost layer of zone of maturation.

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  • An epiphyte is a plant that grows harmlessly upon another plant (such as a tree), fulfill moisture and nutrients from the air, rain and sometimes fro debris accumulating around it, instead of the structure to which it is fastened. Epiphytic organisms usually derive only physical support and not nutrition form their host, though they may sometimes damage the host.

  • Photolysis of water is the outcome of radiant energy taken by plants in which hydrogen ions and oxygen gas are made by the breaking of H2O molecules.

  • Weeping jelly is most often caused by an excess of acid in the fruit or recipe in general. Acetobacter diazotrphicus is more suitable for sugarcane crop than biofertilizers. A halophyte is a plant that grows in waters of high salinity.

  • Phreatophyte is a deep-rooted plant that obtains a significant portion of water that it needs from the phreatic zone or the capillary fringe above the phreatic zone. These plants maintain water status which is largely independent of soil water. Their long roots (up to 25-30 meters length) reaches underground to water table to take water.

  • Cactus, calotropis, aloe etc are desert plants which have the capability to complete their life-cycle even in a dry atmosphere. The rood system of these plants become taller in search of water from the soil and their stems are small, adapted and underground sometimes.

  • A succulent is a plant that stores water for times when water is not available to it. Succulent plants are generally found in arid environment such as deserts and semi-deserts.

  • A xerophyte is a species of plant that has adapted to survive in a dry environment. Opuntia, madar, nerium are the major plants of this type.

  • Bacteria are single-celled microbes. The cell structure is simple than that of other organisms as there is not nucleus or membrane bound organelles. Bacteria are universal, can be found everywhere. There are some harmful bacteria that can cause illness and disease. There are other bacteria that are essential for us to survive. Bacteria in the digestive system also supply needed vitamins like biotin and vitamin K and are our primary source for some of these nutrients.

  • Bacteria are microscopic living organisms. Most of the bacterias are just 2 to 4 micron in size but some of them are 60 longer in size. Some of the microscopic organisms can be seen by a compound microscope as it can magnify an object up to 1500-2000 times.

  • Canola refers to a special type of edible oil which was bred naturally from rapeseed at the University of Manitoba, Canada by Keith Downey and Baldur R. Stefansson in the early 1970s. Canola seeds are used to produce edible oil, which is considered as safe for human consumption. Canola oil has low saturated fat and contains both omega-6 and omega-3 fatty acid. Thus it is good for human health.

  • Triticale is a man-made cereal which is not found in nature. In fact, it is a hybrid small grain produced by crossing wheat and rye. Wheat is use as the female parent and produced by Scotland and Sweden.

  • Leg-haemoglobin is found in root nodules of leguminous plants such as alfalfa and soyabean.

  • Quinine occurs naturally from the bark of the cinchona tree and was used in the treatment of malaria but now it is substituted by Chloroquine. It is a synthetic drug used to kill sensitive malaria parasites.

  • Bats are the mammals of the order Chroptera whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight.

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  • The word “amphibian” is derived from the ancient Greek term amphibians, which means “both kinds of life”. The term was initially used as a general adjective for animals that could live on land or in water. They are ectotherms or co ld-blooded animals, means they are unable to regulate their own body temperature.

  • Sea cow is huge herbivorous sea mammal. Seahorse is a small species of Pisces. Sea lion is also mammal.

  • Human is the smartest creature in the animal kingdom. They are the only creature, who has a desire to learn and the ability to express.

  • Nilgai is the largest Asian antelope species. Antelope are creature, who has strong permanent horns. There are more than 90 species of antelope.

  • Ticks and mites belongs to one of the most diverse groups of class, Arachnids. They have 4 pairs of legs, although some juveniles only have 3 pairs gaining the fourth pair with their first molt. There is no external segmentation of the abdomen, individuals appear as a single body mass.

  • Class of crab –        Malacostraca

Class of mite               –        Arachnida

Class of Scorpion       –        Arachnida

Class of spider            –        Arachnida

  • Opium –        Fruit

Hing          –        Root

Rubber      –        Stem

Quinine     –        Bark

  • Garlic is made up of sulphuric compounds (Ally methyl Sulphide) that render the pungent smell to it. It is also used for treating diaphoretic, diuretic, expectorant, blood pressure and heart disease.

  • Cork is obtained from the bark of the oak tree, whose botanical name is Quercus suber. It is native to the Mediterranean region. Cork consists of irregularly spahed, thin-walled, wax-walled cells.

  • Saffron is a spice derived from the flower of Crocus sativus, commonly known as the “Saffron Crocus”. Saffron is obtained from the style and stigma of the flower of Crocus sativus.

  • In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem.

  • Red chillies are hot because they contain capsaicin. Its chemical formula is C18H27O3.

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Heredity

  • The law of Inheritance was discovered by Gregor Johann Mendel. He is known as the father of modern genetics.

  • Hybridization was experimented on pea plant first by Gregor Mendel. After studying the seven types of qualities of pea, he rendered three rules as-Principle of inheritance, Principle or segregation and Principle of independent assortment.

  • In each cell, molecules of nucleic acid are the most important biological molecules with two categories-Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA). Only viruses have the same category of nucleic acid DNA or RNA. Each cells gets inherited from the parent cell.

  • Mendel’s principle of inheritance is based on sexual reproduction.

  • Gene mapping is the method used for determining the location of gene and relative distances between genes on a chromosome. The essence of all genome mapping is to place a collection of molecular markers onto their respective positions on the genome. Molecular markers come in all forms. Genes can be viewed as one special type of genetic markers in the construction of genome maps and mapped the same way as any other makers.

  • In each chromosome, DNA only has a very long and coiled molecule and the small part of this molecule is called gene. Generally a gene contains 5000 to 100000 pair monomers of DNA molecules.

  • In the descendant of creatures, the hereditary symptoms are moved by chromosomes. These are made from nucleoproteins. The term was coined by Von Waldeyer-Hastz. The small pieces of chromatin during the partition of cells are known as chromosome, on which genes are found.

  • Barbara Mc Clintock was the more profound of jumping genes principle. She was awarded Nobel Prize in 1983 for this special research in medical science while studying of hereditary in the corn plant. He saw that some hereditary element are able to move chromosomes. She found in her study that there are some spots on the maize of corn by the hereditary changes done by jumping genes. Then the conclusion is given that every cell have the part of DNA (transposon) which are important in development.

  • X-ray technicians are more likely to run the risk of a permanent change in their cell’s DNA as compared to others.

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Biofertilizer

  • Bio-fertilizers are defined as preparations containing living cells or latent cells of efficient strains of microorganisms that help crop plants uptake of nutrients, by their interactions in the rhizosphere when applied through seed or soil. They accelerate certain microbial processes in the soil which augment the extent of availability of nutrients in a form easily assimilated by plants. They can be grouped in different ways based on their nature and function.

  • Nitrogen fixing Biofertilizer: Azotobacter, Beijerinkia, Clostridium, Klebsiella, Anabaena, Nostoc, Rhizobium Frankia, Anabaena azollae.

  • Phosphorus solubilizing/Mobilizing Biofertilizers: Bacillus, megatherium var. phosphaticum, Aspergillus, Pezizella ericae.

  • Biofertilzers for micronutrients: Bacillus sps.

  • Plant Growth Promoting Rhizobacteria: Pseudomonas fluorescence, cyanobacteria (blue-green algae) and Azolla are the types of bio-fertilizers. However, Alfalfa is a perennial flowering plant of the pea family.

  • Azolla has the capability of nitrogen-fixing. That is why it is being widely used as a biofertilizer, especially in parts of Southeast Asia.

  • The demand for milk and meat in India is creating a new potential, in profitability of animal husbandry as an occupation. Yet, at some time there is a substantial decline in fodder availability. The search for alternative led to a wonderful plant Azolla which holds the promise of providing a sustainable food for livestock. Azolla, in turn, provides the carbon source and favourable environment for the growth and development of a Algae. It is this unique symbiotic relationship that makes Azolla a wonderful plant with a high protein content.

  • Azolla is an aquatic fern. It gives a good bio-fertilizer when mixed with blue-green algae (BGA) or Cyanoabcteria and contributes in supplying nitrogen to rice field. In addition, they also bring about directly or indirectly a number of changes in the physical, chemical and biological properties of the soil and soil-water interface in rice fields.

  • The Rhizobium japonium bacteria is responsible for the nitrogen fixation in soyabean. Soyabeans inoculated with Rhizobium japonicum strains that synthesized the hydrogenase system fix significantly more nitrogen.

  • 2, 4-Dichlorophenoxyacetic acid (usually referred to by its abbreviation, 2, 4-D) is a common systemic herbicide used in the control of broadleaf weeds. It is one of the most widely used herbicides in the world 2, 4-D is a synthetic auxin (plant hormone) and it is often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium.

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Cell

  • DNA is found in the mitochondria and chloroplast cell organ of cells except of the nucleus, which is a genetic material and carries the symptom signs of creatures to descendants from a parent like a horoscope. Fridrick Meischer (1869) discovered DNA and the double helix model of DNA was given by James Watson and Francis Krick.

  • Prisons are a smallest proteinaceous infectious particle. Myocoplasma is a genus of bacteria that lack a cell wall around their cell membrane. Viroids are smallest infectious pathogens known consisting solely of short strands of circular, single-stranded RNA without protein coast. They are mostly plant pathogens, some of which are of economic importance.  Rickettsia is a genus of non-motile, gram-negative, non-spore forming, highly pleomorphic bacteria.

  • In humans, each cell normally contains 23 pairs of chromosomes, a total of 46. Twenty-two of these pairs called autosomes which are the same in both males and females. The 23rd pair, the sex chromosomes differ between males and females. Females have two copies of the X chromosome (XX) while males have one X and one Y chromosomes (XY).

  • A plant cell is different from animal cell mainly on the basis of the cell wall. The outer shell in a plant cell (which is made from cellulose in green plants) is known as cell wall, which is not found in the animal cell. Except this, green plastids are also found in plant cells while not in animal cells.

  • Three basic and three accessory factors have been recognized to provide genetic variability to the gene pool of a population. Amongst the basic factors, gene and chromosomal mutations have been recognized as the ultimate sources of biological changes and hence, the ultimate “raw material” of evolution. Gene recombination, the third basic factor then increases the variability of individual genotypes in a population.

  • Apoptosis is the process of programmed cell death (PCD) that may occur in multicellular organisms. Apoptosis plays a crucial role in developing and maintaining the health of the body by eliminating old cells, unnecessary and unhealthy cells.

  • Stem cell therapy is the use of stem cells to treat or prevent a disease or condition. Bone marrow transplant is the most widely used stem cell therapy, but some therapies derived from umbilical cord blood are also in use. Research is underway to develop various sources for stem cells and to apply stem cell treatments for neurodegenerative diseases and conditions, diabetes, heart disease and other conditions.

  • The rough endoplasmic reticulum is named as such because its outer membrane is littered with ribosomes. They are responsible for protein synthesis.

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Human Anatomy

  • The amount of water in the human body ranges from 50-75%. The average adult human body is 50-65% water, averaging around 57-60%. The percentage of water in infants is much higher typically around 75-78% water, dropping to 65% by one year of age. Water is the best solvent in nature.

  • Nearby 99% of the mass of human body consists of just six chemical elements: oxygen, carbon, hydrogen, nitrogen calcium and phosphorus. Oxygen is the most abundant element in the human body. It is mainly found in the form of water. Water, in turn, makes up about 60% of the human body and participates in countless metabolic reactions.

  • Almost 99% of the mass of the human body is made up of six elements, these are –

Oxygen     –        65%

Carbon      –        18%

Hydrogen  –        10%

Nitrogen    –        3%

Calcium    –        1.4%

Phosphorus        1.1%

  • The skeleton of an adult human body consists of 206 bones. It is composed of 213 bones in a child, which decreases to 206 bones by adulthood after some bones have fused together. Together these bones form the axial skeleton and the appendicular skeleton.

  • The human skull consists of 28 bones. It consists of two parts, neurocranium and the facial skeleton (also called the viscerocranium). Neurocranium has 8 bones and there are 14 in the viscerocranium (facial bones) and remaining 6 bones occurs in the middle ear, which is helpful in listening.

  • Calcium phosphate is the principal form of calcium found in bovine milk and blood. 70% of bone consists of hydroxyapatite, a calcium phosphate mineral (known as bone mineral). Up to 50% by volume and 70% by weight of human bone is a modified form of hydroxylapatite.

  • The human rib cage is made up of 12 paired (total 24 rib bone) rib bones. Each are symmetrically paired in right and left side. The ribs are flat, thin bones that together with the sternum make up the ribcage. The ribs provide protection for vital organs in the upper body, including the heart and lungs.

  • The stapes is the lightest stirrup- shaped bone and the smallest bone in the human body found in the middle of humans ears. While femur is the largest bone in the human body. It is located in the upper leg which connects the knee at one end and fits into the hip socket at the other.

  • A bone is a rigid organ that constitutes part of the verteberal skeleton. They are light weight but strong, solid and serve multiple functions. There are 62 lowers bones. They consist of 10 hip and leg, 14 ankle and 38 foot bones. The largest and strongest bone in the body in the thighbone (Femur).

  • Blood is a special connective tissue consisting of a fluid matrix, plasma and formed elements. The total volume of blood in normal adult human being is 5-6 liters.

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  • The temperature of human body neither decreases in winters nor increases in summers. The usual temperature of the human body is 98.40 F or 370 C and is controlled by the hypothalamus in the brain. The hypothalamus functions as a type of thermostat for the body.

  • In humans, other mammals and birds, the heart is divided into four chambers: upper left and right atria; and lower left and right ventricles. Commonly the right atrium and ventricle are referred together as the right heart and their left counterparts as the left heart. In a healthy heart, blood flows one way through the heart due to heart valves, which prevent backflow.

  • An electrical impulse generator, called the “sinus node”, sends signals from the right atrium to trigger the heart beat. Like a natural pacemaker, the electrical current follows a web of pathways through the heart, causing the chambers to squeeze and relax in a steady, rhythmic sequence that draws blood into the heart and pulse it out.

  • The lungs are the primary organs for respiration in mammals and most other vertebrates. In mammals, two lungs are located near the backbone on either side of the heart. Its function in the respiratory system is to extract oxygen from the atmosphere and transfer it into the bloodstream and to release carbon dioxide from the bloodstream into the atmosphere, in a process of gas exchange.

  • Each “heartbeat” consists of a contraction and relaxing of the heart muscles. When the heart contracts, it pumps blood through the vessels. When it relaxes, it draws blood in. It takes rest between relaxation and contraction.

  • The amnion is a membrane that covers the embryo. It is filled with amniotic fluid which causes the amnion to expand and become the amniotic sac which serves to provide a protective environment for the developing embryo.

  • Heart rate is the speed of the heartbeats, measured by the number of contractions of the heart typically beats per minute. Our heart beats about 72 times a minute under normal conditions. During sleep a slow heartbeat rates around 40-50 BPM is common. The cardiac cycle refers to a complete heart beat from its generation to the beginning of the next beat. This frequency of the cardiac cycle is described by the heart rate or expressed as beats per minute (BPM).

  • About 4-5 weeks after fertilization, when the heart first begins to beat, the sound of the little heart is too soft to hear. In 4 weeks, the heart typically beats between 105 to 121 times per minute.

  • A sperm remains alive for up to 72 hours after entering into oviduct but its capacity to fertilize the ovum lasts for 48 hours (2 days). So the 12th so 18th days of menstruation cycle is correct for getting pregnancy for a lady because the ovulation (releasing of ovum or secondary socyte from the Graafian follicle of the ovary) happens about the 14th day of the menstrual cycle from any one side of the ovary.

  • The three main parts of the brain are the cerebrum, the cerebellum and the brain stem. The cerebrum is the biggest part of the brain and it is the part that controls movement, thinking, feeling and general problem-solving abilities. The cerebellum is smaller than the cerebrum. This part of the brain sits at the back of your skull, underneath the cerebrum. The cerebellum is responsible for controlling co-ordination and balance. The hippocampus is the part of the cerebrum that deals with memory.

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  • Breast bone –        Sternum

Collar bone        –        Clavicle

Knee cap            –        Patella

Shoulder blade   –        Scapula

  • In human life span, 20 teeth developed twice. Like a human, most of the mammals are diphyodont. It means our 12 permanent molars are monophyodont and others diphyodont. There are four type of teeth – Incisors, canine, premolars and molars.

  • Tooth enamel is the thin outer covering of the tooth and the strongest part of our body. It makes our teeth white and it exists to protect the crowns of healthy teeth. Tooth decay is due to the destruction of tooth enamel. It is made up of hydroxyl-apatite crystals, which is calcium phosphate.

  • Nails are usually made of thick and multiple layers of a type of protein known as a- keratin and are composed of dead tissues. They are devoid of any nerves and blood vessels and therefore we do not feel any pain while the nails are being cut.

  • Dental plaque is a biofilm or mass of bacteria that grows on surfaces within the mouth. It appears as a white/pale yellow “slime layer” commonly found in between the teeth and along the cervical margins. Plaques formed on teeth are made up of food particles, saliva, mouth acids and bacteria in the oral cavity. Saliva has a normal pH range of 6.2-7.6 with 6.7 being the average pH.

  • Excretion of average urine in the adult human body is around 1.5 liters of urine per day. About 91-96% of urine consist of water.

  • The spine is a mixed nerve which carries motor, sensory and autonomic signals between the spinal cord and the body. In human there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the corresponding cervical, thoracic, lumbar, sacral and coccygeal regions of the spine. There are eight pairs of lumbar nerves, five pairs of sacral nerves and one pair of coccygeal nerves. The spinal nerves are part of the peripheral nervous system.

  • A ligament is a tissue that concepts two bones to form a joint. It is tough and fibrous which means that when it is formed, a ligament can take quite a while to heal might even require surgery.

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Blood Transport System

  • Blood is a liquid connecting tissue. If flows inside the blood vessels and is viscous thick fluid. The function of blood is to transport oxygen and carbon dioxide. Actually blood carries away oxygen from lungs towards the body tissues and carries carbon dioxide from there, to take towards lungs.

  • Hemoglobin is the protein molecule in red blood cells that carries oxygen from the lungs to the body’s tissues and returns carbon dioxide form the tissues back to the lungs.

  • An earthworm is one of the animals that are classified in the Annelida phylum. In an earthworm, hemoglobin is dissolved in the plasma. The earthworm has a closed circulatory system in which blood is confined to blood vessels which recirculates again and again to get maximum use of it.

  • Red Blood Cells (RBCs) or red blood corpuscles also called erythrocytes are the most common type of blood cell and the vertebrate organism’s principal means of delivering oxygen (O2) to the body tissues- via blood flow through the circulatory system. RBCs take up oxygen in the lungs or gills and release it into tissues while squeezing through the body’s capillaries. The cytoplasm of erythrocytes is rich in haemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red colour of the cells.

  • The red colour of red blood cells in the blood is due to the combining of a protein as haemoglobin wit oxygen. Red blood cells are also called erythrocytes which are found only in the blood of vertebrates. There is no nucleus inside the red blood cells.

  • Blood performs many important functions within the body including supply of oxygen to tissues (bound to haemoglobin, which is carried in red cells) the supply of nutrients such as glucose, amino acids and fatty acids (dissolved in the blood or bound to plasma protein) e.g. blood lipids.

  • Ideally, a normal human must have a blood pressure (120/80). This means that systolic pressure around 120 mm Hg and diastolic pressure should be around 80 mm Hg.

  • “Hg” is a symbol of Mercury, a chemical element. It is used in thermometers, barometers, nanometers, sphygmomanometers and other devices. A sphygmomanometer is a device used to measure blood pressure. The person’s blood pressure is measured in millimeters of mercury (mm Hg). Normal blood pressure of human body is 120/80 mmHg.

  • Here blood pressure of Mr (Y) is normal because normal blood pressure in humans is generally 120-80, i.e. systolic pressure 120 and diastolic pressure 80. Blood pressure of Mrs (X) is less than normal but remaining others have blood pressure more than the normal.

  • Individuals with blood group “O” are a universal donor because their red blood cells have neither A nor B antigens on their surface. So the blood of a person having O group can be given to people with any blood group.

  • Blood group A individuals have the A antigen on the surface of their RBCs and blood serum containing IgM antibodies against the B antigen. Therefore, group A individual can receive blood only from individuals of groups A or O (with A being preferable) and can donate blood to individuals with type A or AB.

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  • There are four main blood groups defined by ABO system –

  1. Blood group A – has A antigens on the RBC with anti-B antibodies in the plasma.

  2. Blood group B – has B antigens with anti-A antibodies in the plasma.

  3. Blood group AB – has both A and B antigens, but no antibodies.

  4. Blood group O – has no antigens, but both anti- A and anti- B antibodies in the plasma.

 

  • Karl Landsteiner was an Austrian biologist and physician. He is noted for having first distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups his identification of the presence of agglutinins in the blood and having identified with Alexander S. Wiener, the Rhesus Factor in 1937, thus enabling physicians to transfuse blood without endangering the patient’s life.

  • As the blood group of couple is AB positive and O , twin boys were born to them will have  A+ and B negative or BA+. Therefore, blood group of the adopted son is O+    

  • If among the parent blood group of the father is A and blood group of the mother is “O” then the blood group of the son will be “O”. Bernstein in 1924 discovered that blood group AB, O in humans represents genetic characteristic and develop according to Mendel’s laws, in offsprings by getting genes from parents.

  • Blood pH is regulated to stay within the narrow range of 7.35 to 7.45, making it slightly basic. Blood that has a pH below 7 is acidic, whereas blood pH above 7.45 is too basic.

  • White Blood Corpuscles (WBCs) are disease-fighting cells found in blood. When our blood is infected by any harmful bacteria or virus at any place in the body, white bloods corpuscles reaches there and eats up or destroys these harmful outsiders.

  • The number of leukocytes in the blood is often an indicator of disease. The normal white blood cell count is 4000-11000 per micro liter of blood. They make up approximately 1% of the total blood volume in a healthy adult. An increase in the number of leukocytes over the upper limits is called leukocytosis, and a decrease below the lower limit is called leukopenia. The diameter of W.B.C. in human body is about 0.007 mm.

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  • Lymphocytes produce antibodies or resisting protein is blood plasma and are responsible for inactivating poisonous substances. Lymphocytes are very small white blood cells with large nucleus wanders in the whole body and their number is large in comparison of total W.B.C. count (about 25%). Like an army, lymphocytes protect the body by coordinating with all parts of the immune system.

  • Leukemia is a group of cancer that usually begins in the bone marrow and results in high numbers of abnormal white blood cells. These white blood cells are not fully developed and are called blasts or leukemia cells. Symptoms may include bleeding and bruising problems.

  • Human blood contains plasma, R.B.C. and W.B.C. with some proteins (albumin, fibrinogen) etc. Blood plasma contains 92% of water and in other 8.5%, there are proteins like mentioned above some electrolytes.

  • Alum is a specific crystalline substance and the aluminium ion present in it has high coagulating property. So, the alum is considered very good for the coagulation of blood when someone gets wounded and blood starts coming out from the wound.

  • Getting oxygen to the body’s cells requires three major events:

  1. Uptaking oxygen from the air to the lungs

  2. Transporting that oxygen in the blood

  3. Delivering the oxygen to cells throughout the body

  • Platelets help in the blood clotting process (or coagulation) by gathering at the site of an injury, sticking to the lining of the injured blood vessel and forming a platform on which blood coagulation can occur. Platelets are only about 20% of the diameter of red blood cells. The normal platelet count is 150,000-350,000 per microliter of blood, but since platelets are so small they make up just a tiny fraction of the blood volume. The ratio of platelets to red blood cells in a healthy adult is 1:10 to 1:20. Red blood cells are the most numerous blood cell, about 5,000000 per micro liter. Red blood cells make up about 40% of our total blood volume, a measure called the hematocrit. White blood cells are the largest of the blood cells but also the fewest. There are only 5000 to 10000 white blood cells per micro liter.

  • Biological Oxygen Demand (BOD) is a standard criterion for pollution assay in aquatic ecosystems. Organic and inorganic waste utilizes soluble oxygen is water bodies to decompose, which reduces the amount of soluble oxygen in water. The decrease in the amount of soluble oxygen in water. The decrease in the amount of soluble oxygen increases its demand. More BOD indicates water is being infected. Therefore, the demand for oxygen is directly related to the amount of increasing waste. This demand is called as BOD. Where there is high BOD, there will be low dissolved oxygen.

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Digestion and Excretion

  • Digestion begins in the mouth when we chew and swallow and is completed in the small intestine. The small intestine. The small intestine is a long tube loosely coiled in the abdomen (spread out, it would be more than 20 feet long). The small intestine continues the process of breaking down food by using enzymes released by the pancreas and bile from the liver.

  • Saliva is a watery substance located in the mouths of man and animals, secreted by the salivary glands. Human Saliva is 99.5 % water, while the other 0.5% consists of electrolytes, mucus, glycoproteins, enzymes (amylase) and antibacterial compounds such as secretory IgA and lysozyme. The enzymes found in saliva are essential to begin the process of digestion of dietary starches.

  • Cellulose is the most commonly found organic compound, biopolymer and polysaccharide on the earth. Each of these molecules contains approximately 10 to 15 thousand glucose molecules in the form of an inosculated homopolymer series. Starch plants have structural polysaccharides which contain two types of homopolysaccharide molecules made of glucose cells –

10 to 30 percent amylase and 70 to 9 percent amylopectin molecules

  • Kidneys remove excess organic molecules from the blood and it is by this action that their best-known function is performed; the removal of waste products of metabolism. They serve the body as a natural filter of the blood and remove water-soluble wasters, such as urea and ammonium and they are also responsible for the reabsorption of water, glucose and amino acids.

  • The kidneys are two bean-shaped organs that extract waste from blood, balance body fluids from urine and acid in the other important functions of the lady. The nephron is the basic, structural and functional unit of the kidney. A nephron eliminates waste from the body, regulates blood volume and blood pressure. Reabsorption of vital nutrients like glucose at normal plasma levels is completely reabsorbed in the proximal convoluted tubule.

  • The process, utrafiltration occurs at the barrier between the blood and the filtrate in the renal capsule in the kidney. The kidneys remove urea and other toxic wastes from the blood, forming a dilute solution called urine the process.

  • Dialysis is a process for removing waste and excess water from the blood and is used primarily as an artificial replacement for lost kidney function in people with kidney failure. Dialysis filters out unwanted substances and fluids from the blood.

  • In humans, kidney is the main organ of the excretion system. Filtering the blood and removing unnecessary and waste products from the body is the basic function of kidney.

  • Urea is an organic compound whose chemical formula is CO (NH2)2. Nearly 46.7% of nitrogen in the urea is present in the form of amide. In the field of organic chemicals it is also called carbamide.

  • The main function of the pancreas is to produce insulin hormones.

The pancreas plays on important role in digestion and in regulating blood sugar level in the blood, while other three are the normal function of human kidneys.

  • Kidneys are the most important organ in our body. Kidneys help in purification of blood and also removes toxic materials from our body through urine. Our kidneys purify around 1500 liter of blood and convert it into approximately 1.5 liter urine per day. 1200 ml of blood flows through both kidneys per minute and out of it 1 ml of urine is formed per minute.

  • Calcium Oxalate is a chemical compound that forms envelope-shape crystals, known in plants as raphides. A major constituent of human kidney stones is calcium oxalate.

  • Restriction endonuclease Eco RII (pronounced eco R two) is an enzyme of restriction modification system (RM) naturally found in Escherichia coli are a special class of enzyme that recognize and cleave (cuts) DNA at specific places. They produce small well-defined fragments of DNA that help to characterize genes and genomes and that produce recombinant DNAs.

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  • The term “nutraceutical” is used is used to describe any food or part of food supplements that offers a medical or health benefit beyond simple nutrition. Such benefits many include the prevention or recurrence of the disease.

  • The small intestine is divided into three structural parts. The duodenum is a short structure (about 20-25 cm long) continuous with the stomach and shaped like “C”. It surrounds the head of the pancreas. The duodenum contains Brunner’s glands, which produce a muscus-rich alkaline secretion containing bicarbonate. These secretions, in combination with bicarbonate from the pancreas, neutralizes the stomach acids contained in the gastric chyme.

Photosynthesis

  • Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. In this process, CO2 is taken in from the atmosphere and oxygen (O2) is released out during the formation of glucose.

  • Oxygen gas produced by photosynthesis comes from water and not from carbon dioxide.

  • Plants use only certain colours from light for the process of photosynthesis. The chlorophyll absorbs blue, red and violet light rays. Photosynthesis occurs more in blue and red light rays and less or not at all in green light rays. The light that is absorbed the best is blue due to the presence of carotenoids pigment in plants and Algae.

  • 90% of the photosynthesis on earth is done by aquatic plants and algae. Among these, 85% of these is in the sea (mainly by algae) and remaining 5% is in river, ponds etc. In the process of photosynthesis, CO2 (carbon dioxide) is absorbed and carbohydrate and oxygen are produced.

  • The process of photosynthesis takes place only in the visible part (3800 A0-7600A0 wavelengths) of the electromagnetic radiations. Best photosynthesis takes place in the red light and next best blue light and in green light, it is nill. T.W. Engelmann ( 1888), had shown the action spectrum of photosynthesis in his experiment, in which algae in red light produces more oxygen and represented by the accumulation of more aerobic bacteria, whereas in blue light some fewer numbers of bacteria were accumulated.

  • Through the process of photosynthesis, green plans have a capacity of manufacturing their food from simple substances as CO2 and H2O in presence of light. Normally, plants utilize sunlight (day) but marine algae also use moonlight. Photosynthesis even occurs in electric light.

  • In the process of photosynthesis, light energy changes into the chemical energy. Normally plants utilize sunlight but marine algae also use moonlight, photosynthesis even occurs in electric light.

  • On earth, the main source of energy is sunlight which is transformed by photosynthesis into a form of chemical energy that can be used by photosynthetic and non-photosynthetic organisms alike. By converting the energy of sunlight to a usable form of potential chemical energy, photosynthesis is the ultimate source of metabolic energy for all biological systems.

  • Phloem also called “bast” tissues in plants that carry food produced in the leaves to all other parts of the plant. Phloem is composed of various specialized cells called sieve tubes, companion cells, phloem fibres and phloem parenchyma cells.

  • Photosynthesis takes place in leaves which prepare food for the plants by absorbing light CO2 and water. Generally root cells do not contain chloroplasts; so is no chance of photosynthesis.

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Vitamins and Nutrition

  • Kazimierz Funk is generally credited with being among the first to formulate the concept of vitamins, which he called “vital amines” or “vitamins”. Umetaro Suzuki had in 1910 succeeded in extracting a water-soluble complex of micronutrients from rice bran and had named it “aberic acid”.

  • Vitamins are organic compounds and a vital nutrient that an organism require in limited amounts. An organic chemical compound (or related set of compounds) is called a vitamin when the organism cannot synthesize the compound in sufficient quantities and must be obtained through the diet.

  • Ample amount of potassium, sodium, magnesium, calcium sulphur and chlorine etc. are known as macronutrients whereas micronutrients are needed in a small amount for the organism.

  • Fredrick Gowland Hopkins was the first scientist to elucidate the “accessory food factor”, the idea that food contains trace amounts of substances essential for nutrition. Accessory food factors later came to be called vitamins.

  • Fats have highest calorie value per unit because of its higher rate of oxidation due to less oxygen. 400 kilocalorie energy is obtained by metabolic oxidation of 1 gm carbohydrate or protein whereas 9.3 k-calorie is received by fats from the same amount. Flora and fauna, both are a source of fats.

  • Essential elements are classified into following two categories –

  1. Macroelements (Major elements) – These are required by the plant in larger quantities eg. – Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), Potassium (K), Magnesium (Mg), Calcium (Ca) and Sulphur (S).

  2. Microelements (Minor elements or trace elements) – These are required by the plant in low quantities. Example are Boron (B), Zinc (Zn), Manganese (Mn), Copper (Cu), Molybdenum (Mo), Chlorine (Cl), Iron (Fe) and Nickel (Ni).

  • Beri-Beri disease is caused by a deficiency of Vitamin B1 whose chemical name is Thiamin. Riboflavin is the chemical name of Vitamin B2 which is responsible for stomatitis and malnutrition.

  • Potassium is an electrolyte, which is a mineral that has an electric charge. It plays an important role in maintaining a healthy heart rhythm through muscle action. Apple trees absorb potassium in a greater amount than any other nutrient, so apples are a rich source of potassium.

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  • Vitamin “C” occurs in various fruits like lemon, orange, gooseberry etc. Vitamin C is water-soluble vitamin which is necessary for normal growth and development. Ascorbic acid is the chemical name of Vitamin C. Deficiency of this vitamin causes of disease Scurvy in human.

  • Vitamin A is the major constituent of milk, ghee and is enriched by fats and pulses which are the rich source of protein. Raw and citrus fruits are a major source of vitamin C.

  • Gooseberry, orange, tomato, lemon, papaya, peas etc. are a rich source of Vitamin C (Ascorbic Acid). It is an important antioxidant which helps to protect against cancer, heart diseases, stress, maintaining a healthy immune system and wound healing process. It is essential for sperm production and formulation of collagen. The collagen protein involved in the building and health of cartilage, joints, skin and blood vessels etc.

  • The body cannot store Vitamin C. Most vitamins are fat soluble, which means they bond with fat molecules and can be stored in the body’s organs (particularly the liver and kidneys), tissues or blood for long periods of time. Vitamin C, on the other hand is actually water soluble and bonds instead of water, which is flushed out of the body via the urine rather quickly.

  • Vitamin K is a responsible factor for blood coagulation and also certain proteins that the body uses to central binding of calcium in bone and other tissues. Without vitamin K, blood coagulation is seriously impaired and uncontrolled bleeding occurs. Vitamin K is known as antihaemorrahgic factor.

  • Blood is a fluid connective tissues which coagulates in few minutes after ejecting from the body which called as blood clots. In process of blood clots. In process of blood clotting; energy, adrenaline, thrombin, calcium chlorine and Vitamin K are involved.

  • Antidote to anticoagulant poisons – Vitamin K is used as anticlot. This vitamin is called antihemorrhagic factor. Operation of persons with deficiency cannot be done easily because there is a fear of excess bleeding.

  • Vitamin B12 vitamin K both are synthesized by bacteria in human intestine.

  • The source of Vitamin D is sun rays. In fact, vitamin D is synthesized in our dermal cell by rays which is released in the blood. Besides of sun rays, Vitamin D is obtained from butter, the yolk of egg, liver and kidney etc. Rickets in children and osteomalacia in adults occur due to deficiency of Vitamin D. Together with Calcium deficiency of vitamin D causes osteoporosis in older adults.

  • Vitamin A is needed by the retina of the eye in the form of retinol, which combines with protein opsin to form rhodopsin, the light absorbing molecules necessary for both low light (scotopic vision) & colour vision.

  • The wheat germ oil is extracted from the germ of the wheat kernel which makes up only 2.5% by weight of the kernel. Wheat germ oil has the highest content of Vitamin E. It is a fat-soluble vitamin and plays a role as an antioxidant in the body.

  • Vitamin A is largely stored in the liver in the human body. The chemical name is retinol whose deficiency causes night blindness.

  • Carrot is the richest source of vitamin A. Spinach is a major source of iron which contributes to the level of haemoglobin concentration, beneficial for oxygen transportation.

  • Thiamine (Vitamin B1) is a water-soluble vitamin that is necessary for carbohydrate and amino acid metabolism. Its main sources are rice bran, whole wheat flour, eggs, yeast, meat, etc. Thiamine deficiency results in beri-beri, a disease characterized by multiple neuritides, general debility and heart failure.

  • Vitamin B12 (Cyanocobalamin) is a water soluble vitamin. It contains a metallic ion cobalt. Its chemical formula is C63H88CoN14O14 It functions as a factor for enzymes in the metabolism of amino acids and fatty acids, required for new cell synthesis, normal blood formation and neurological function. Its deficiency causes pernicious anaemia, nervous symptoms etc.

  • Vitamin B and C are water soluble vitamins whereas A, D, E and K are fat-soluble vitamins.

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  • Vitamins B1 (Thiamine) –        Beri-Beri, Wernicke-Korsakoff syndrome

Vitamin D (Ergocalciferol, Cholecalfiferol) – Rickets and Osteomalacia

Vitamin C (Ascorbic acid)  –        Scurvy

  • Sunlight and cod-liver oil are rich source of vitamin-D. Wheat germ oil is rich vitamin-E while Alfalfa is rich in vitamin-K. Though orange is rich in Vitamin-C but it is very low source of vitamin-B1.

  • Rickets is caused by deficiency of Vitamin D, Beri-Beri is caused by a deficiency of B1. Nyctalopia or night blindness is causes due to deficiency of vitamin A and scurvy is caused due to deficiency of Vitamin C.

  • Vitamin C –        Scurvy

Folic Acid          –        Anaemia

Vitamin A          –        Night blindness

Vitamin B1         –        Beri-Beri

  • Colour blindness is a sex-linked genetic disorder. It does not relate to vitamin D. The deficiency of Vitamin D causes rickets and osteomalacia. The deficiency of Vitamin A causes night blindness. Vitamin B3 is also called niacin or vitamin “PP”. Its deficiency causes pellagra. The deficiency of folic acid causes anaemia.

  • Napthoquinone is the chemical name of Vitamin-K. It is known as anti-haemorrhagic factor. Its sources are green leaves, egg, liver & intestinal bacteria etc. Sterility is related with deficiency of vitamin E.

  • Retinol –        Conjunctivitis

Tocopherol         –        Sterility

Cyanaocobalamine     Pernicious anaemia

Pyridoxine         –        Mental illness

  • Ptyalin –        An enzyme in the saliva that converts starch into dextrin and maltose.

  • Pepsin –        An enzyme that splits proteins into proteoses and peptones.

  • Renin –        A proteolytic enzyme secreted by the kidneys that convert angiotensinogen into angiotensin

  • Oxytocin –        A polypeptide hormone, produced by the posterior lobe of the pituitary gland that stimulates contraction of the smooth muscle of the uterus.

  • Soyabean is richest source of protein. It contains 40% protein. It is classified as an oilseed as well as pulse crop. The milk is produced by soyabean which is equivalent to the milk of a cow. Each grain of soyabean contains 40% protein, 20-23% fat and 30% carbohydrate.

  • The groundnut is a rich source of proteins and fat. Groundnut contains 25.3% protein and 48.1% fat. In groundnut, protein 1.3 times of meat, 2.5 times of eggs and 8 times of fruits is found.

  • Eating trans-fat raises the level of low-density lipoprotein (LDL) or bad cholesterol and lowering the level of HDL or good cholesterol, which increases the risk of developing cardiovascular diseases. The animal fats/oil and hydrogenated oils are the forms of trans fat.

  • Generally water an inorganic substance is most abundant in living beings. But in organic compounds, protein is most abundant because they are one of the building blocks of body tissues and can also serve as a fuel source.

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  • Fats have the highest energy value since 1 g of fat contains 9.3 kcal (37 kj) of energy; one gram of protein contains 5.4 kcal; one gram of carbohydrates contains 4.2 kcal of energy.

  • Fat present below the skin surface of our body forms a complete barrier against the external environment. It is an energy store and also acts as a thermal insulating layers. It protects the underlying structure of the body from any physical trauma.

  • Milk contains 87% water, protein, vitamin A, Vitamin B12, Vitamin B6, Riboflavin, carbohydrate, Calcium (Ca) and potassium (K) etc. Thus milk is an ideal diet containing almost all nutritious elements.

  • Alpha-linolenic acid a king of omega-3 fatty acid found in plants. It is found in flaxseed oil, canola, soyabean and walnut oil.

  • Glycine, serine and tryosine are non-essential amino acids, which are produced inside our bodies. There are 20 biologically active amino acids found in human body. These are divided into two categories-10 are essential amino acids and 10 are non-essential amino acids. Essential amino acids are those which can’t synthesize inside the human body.

  • Linseed is a food and fibre crop that is grown in cooler regions of the world. The oil is extracted from its seed, known as linseed oil, which is a very good source of omega 3 fatty acid, which is able to prevent the deposition of fat in blood vessels.

  • Vitamins and minerals are often called micronutrients because our body needs only tiny amounts of them. Cereals, green vegetables, milk, fruit and meat are a good source of vitamins. White blood cells help to keeps the body healthy by destroying harmful bacteria.

  • The cells of human body can synthesize most of the fatty acids. However only essential fatty acids cannot be synthesized in the body.

  • Malnutrition is a condition that results from eating a diet in which nutrients are either not enough or are too much such that diet causes a health problem.

  • Starch and cellulose are two very similar polymers. In fact, they both are made from the name monomer, glucose (C6H12O6) and have the same glucose-based repent units. Starch gives blue-black colour in an iodine solution, whereas cellulose give no colour in this solution. Starch is an important component of stored food of plants, whereas cellulose is found in the cell wall of plants.

  • Milk contains all the vitamins of the B- vitamin category such as B1, B2 and B6, B12.

  • Starch is a polymeric carbohydrate consisting a large number of glucose units joined by glycoside bonds. This polysaccharide is produced by most green plants as an energy store.

  • About 10% to 15% protein in a daily diet is required by a lactating mother. It is near about 65 to 75 gram protein.

  • Protein after water are the most abundant constituent of protoplasm. They are made up of carbon, oxygen, hydrogen and nitrogen but sulphur, iodine, iron and some other elements may also be found in them in traces. Proteins are long chain compound; their simple components or basic building unit are the amino acids. A simple protein consists of about 100 amino acid molecules. However, their number varies from 300-1000 in different proteins.

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  • We need protein for our muscles, bones and the rest of our body. Exactly how much protein we need respect to our age are given below –

  • Babies need about 10 grams per day.

  • School-age kids need 19-34 grams per day.

  • Teenage boys need up to 52 grams per day.

  • Teenage girls need 46 grams per day.

  • Adult men need about 56 grams per day.

  • Adult women or moderately active woman – need about 46 grams per day (65-70 grams, if pregnant or breast- feeding).

  • Golden Rice is the achievement in the field of biotechnology by Prof. Ingo Potrikus and Dr. Peter Beyer. The colour of this rice is golden. Two genes of daffodil and one gene of Erwinia uredovora is inserted in its genom. These three genes produce the enzymes needed to convert naturally occurring compounds into the immature embryoids of rice, that convert Geranylgerranyl-diphosphate (GGDP) into beta carotene. On reaching in our body beta carotene converts into Vitamin-A which is very useful for our eyes.

  • Vitamin Chemical Name

Vitamin A          –        Retinol

Vitamin B1         –        Thiamine

Vitamin B2         –        Riboflavin

Vitamin B3         –        Niacin

Vitamin B5         –        Pantothenic acid

Vitamin B6         –        Pyridoxine

Vitamin B7         –        Biotin

Vitamin B9         –        Folic acid

Vitamin B12        –        Cyanocobalamin

Vitamin C          –        Ascorbic acid

Vitamin D          –        Calciferol

Vitamin E          –        Tocopherols

Vitamin K          –        Phylloquinone

  • Chrisopher Columbus called papaya “The fruit of the angel”. One medium size (276 gram) Papaya contains vitamin C (224%) that is two to three times more than our recommended daily and it is an excellent source of folate (26%), fibre (19%), Vitamin A (15%), magnesium (14%), potassium (14%), copper (13%) and poatothenic acid (11%).

  • Vitamin B12 –        Cobalt

Haemoglobin     –        Iron

Chlorophyll        –        Magnesium

Chalco pyrite     –        Copper

Table salt           –        Sodium chloride

Washing Soda    –        Sodium carbonate

Brass                  –        Copper

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  • Lactose is a disaccharide sugar derived from glucose and galactose. It is responsible for imparting sweetness to milk.

  • The yellow colour of cow’s milk is due to the presence of carotene. It is a hydrocarbon whose formula is C40H56. It is found in hay, grass, green leaves, some fruits, carrots etc. When cow consumes carotene containing foods, some of the pigment is converted into vitamin A and some found unchanged in milk. Vitamin A imparts no colour to milk, whereas carotene gives milk a yellow colour.

  • Spinach has a high nutritional value for the human body. It is a rich source of Iron and Calcium. According to the United State Department of Agriculture, 180 gram serving of boiled spinach contains 6.43 mg of iron, whereas one 170 gram ground hamburger patty contains at most 4.42 mg. Thus, spinach contains a relatively high level of iron, compared to other vegetables and meat sources.

Endocrine Glands, Hormones

  • Progesterone hormones are related to uterus and menstrual cycle of female. Testosterone is secreted by testis of male. Thyroxine is secreted by thyroid gland, Insulin is secreted by pancreas.

  • Secretin is a hormone that stimulates pancreas for the production of digest juice. Secretin also helps to regulate the pH of the duodenum by inhabiting the secretion of gastric acid from the parietal cells of stomach. It also stimulates the contraction of the pancreas.

  • The pancreas is a mixed gland which secretes digestive enzyme and the beta cells of islets of langerhans secrete insulin, alpha cells secrete glucagon, delta cells secrete somatostatin hormone. If the pancreas is defective by any of the reason, then the formation of insulin and glucagon are affected badly.

  • Even though a living being is fed with carbohydrate rich diet, its blood sugar concentrating tends to remain constant. It is because the beta cells of pancreas secrete insulin hormone which reduces blood glucose concentration. Diabetes is caused by the lack of insulin hormone in our body, while too much insulin leads to abnormally low blood glucose level or hypoglycemia.

  • Insulin is a peptide harmone, produced by beta cells in the pancreas and is essential to regulate carbohydrate and fat metabolism in the body. It causes cells in the muscles and fat tissue to absorb glucose from the blood.

  • Drinking of whiskey increases the frequency of urination because it behaves like a diuretic substance that increases urine production in the body. Alcohol also suppresses a pituaitary gland hormone (ADH) which is responsible for inhibiting the diuretic effect. This makes our kidneys unable to reabsorb as much liquid as usual. This result is a substantial increase in urine output.

  • Plant hormones are naturally occurring special organic compounds found in plants. They affected and control many metabolic activities after being transported to different parts of the plants in very low quantity. Auxins, Gibberellin, Cytokinin, Abscisic acid, and Ethyline are some examples of the plant hormone.

  • A hormone produced in the pancreas by islets of Langerhans, which regulates the amount of glucose in the blood. The lack of insulin causes diabetes.

  • Insulin is a hormone which plays an important role in the regulation of blood glucose level. The main source is insulin from the roots of dahlias and Beta b-cells of the pancreas.

  • The liver is the largest gland of the human body. Extra glucose in the body gets converted into glycogen and is stored in the liver. Glucose is a simple sugar found in carbohydrates. Once carbohydrates are absorbed from food, they are carried to the liver for processing.

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  • The plant hormones are generally classified into five groups, These are –

  1. Abscisic acid

  2. Auxins

  3. Cytokinins

  4. Ethylene

  5. Gibberellins

  • Under prevention of food adulteration rule, 1955 (Act 44AA) acetylene gas can be used in the ripening of fruits. Calcium carbide is used in some countries as a source of acetylene gas, which is an artificial ripening agent. However, acetylene is not nearly as effective as ethylene and is not a natural plant hormone-like ethylene. Also, calcium carbide may contain traces of arsenic and phosphorus, both highly toxic to humans and the use of this chemical for ripening is illegal in most countries. Ethylene has been found not harmful or toxic to humans in the concentrations found in ripening rooms.

  • Bile is fluid that is made and released by the liver and stored in the gallblader. It is stored and concentrated in the gallblader unit which is needed to digest food. In adults, the gallblader measures approximately 8 centimetres in length and 4 centimetres in diameter.

  • Parathyroid hormone (PTH), secreted by the chief cells of the parathyroid glands as a polypeptide containing 84 amino acids. Parathyroid hormone regulates serum calcium through its effects on the tissues. PTH reduces the reabsorption of phosphate from the proximal tubule of the kidney, which means more phosphate is excreted through in the urine.

  • Fructose is also known as fruit sugar. This type of sugar is mainly found in fruits. Fructose is a monosaccharide.

  • TIVA, a growth hormone widely used to reduce flower dropping in pulses to enhance production.

  • Ethylene is a phytohormone (plant hormone) which is found in gaseous form.

  • Oxytocin has two target tissues – women’s uterus and their breast. Oxytocin stretches the cervix and uterus during labour and stimulates the nipples for breastfeeding. Oxytocin also plays a role in release of milk from mammary glands.

  • Hormone –        Testrogen

Enzyme              –        Lipase

Phospholipid      –        Lecithin

Polymer             –        Polythene

  • Goiter is a disease caused by the deficiency of iodine and is characterized by the enlargement of thyroid gland present in our neck. It is an endemic disease and mostly affects people living in hilly areas. Hilly areas are naturally iodine-deficient due to poor iodine content present in the soil, water and agriculture produce.

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  • Iodised salt is useful as it controls the thyroid gland.

  • Adrenaline                 –        Anger, fear, danger

Estrogen                      –        Females

Insulin                         –        Glucose

Pheromones                –        Attracting partners through the sense of smell

  • The hyphothalamus is a section of the brain responsible for hormone production. The hormones produced by this area of the brain governs body temperature, thirst, hunger, sleep, circadian rhythm, moods, sex drive and the release of the other hormones in the body.

  • Gastrin is a peptide hormone which stimulates secretion of gastric acid by gastric cells.

  • Adrenaline is commonly known as the “fight or flight hormone”. Adrenaline is a hormone released from the adrenal glands and its major action together with nor-adrenaline is to prepare the body for fight or flight. Adrenaline (Epinerphrine) causes dilation of blood vessels (Vasodilation) which supply the brain, skeletal muscles, heart, lungs, liver, adipose tissues, sensory organs etc. Due to increased blood supply. These organs become very active and excited including alarm reaction, concentration of cardiac muscles intensify, increasing both rate and force of heartbeat, pulse rate, arterial pressure and cardiac output.

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Physiology

  • The acid produced by ants is called formic acid. Chemically it is a simple carboxylic acid.

  • The whale is marine mammals of the order Cetacea. They are warm-blooded and have a layer of fat or blubber under the skin. Their forelimbs are modified into flippers.

  • The lung is a main respiratory organ, which maintains the body temperature through breathing inhaling oxygen – rich air and exhaling air filled with carbon dioxide which is a waste gas. In this process, the water of the body is vapourised, which maintains the body temperature.

  • The average of normal temperature of human body is 98.40 F (370C).

  • Plants are propagated by two methods –

  1. Sexual propagation or seed propagation.

  2. Asexual or vegetative propagation.

  • Cascuta (dodder) is a genus of about 100-170 species of yellow, orange or red plant parasite plant. Dodder can be identified by its thin stems-appearing leafless, with the leaves reduced to minute scales. The dodder produces haustoria. It is used in traditional medicine as a purgative and to treat disorders of the liver, spleen and urinary tract.

  • Melatonin is a hormone secreted by the pineal gland in the brain. It helps to regulate other hormones and maintains the body’s circadian rhythm. The circadian rhythm is an internal 24-hour “clock” that plays a critical role at the time when we fall asleep and when we wake up. When it is dark, our body produces more melatonin. When is bright, the production of melatonin drops.

  • Layering is a way to grow new plants as in case of jasmine (from existing plants without having to take any cuttings.) In a nutshell, bury part of a stem or branch in the soil and new roots and shoots will form. Grafting or graftage is a horticultural technique where by tissues from one plants are inserted into those of another so that the two sets of vascular tissues may join together.

  • The medulla oblongata which is three centimetre long connects the higher levels of the brain to the spinal cord and is responsible for several functions of the autonomous nervous system which include: Reflex centers of vomiting, coughing, sneezing and swallowing. These reflexes which include the pharyngeal reflex, the swallowing reflex (also known as the palatal reflex) and the master reflex can be termed, bulbar reflexes.

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Disease and Treatment

  • Arthritis is caused be deposition of uric acid crystals (mono-sodium urate) in joints and fluids with the body gout, is a painful form of arthritis.

  • Dropsy disease in characterized by swelling of the body tissues due to the accumulation of fluids. When the mustard oil is adulterated deliberately (as in most cases) or accidentally with argemone oil, proteinuria occurs. In mustard, the adulteration like a mixture of cyanide mixing of white colour usually happens.

  • Cancer is a disease involving abnormal cell growth with the potential to invade or spread to other parts of the body. Not all tumors are cancerous; benign tumors do not spread to other parts of body. Possible signs and symptoms include a new lump, abnormal bleeding, a prolonged cough, unexplained weight loss and a change in bowel  movements etc. While these symptoms may indicate cancer, they may also occur due to other reasons. There are over 100 different types of known cancers that affect humans.

  • Leafs Parthenium hysterophorus plant exhibits significant medical attributes including anti-cancer property.

  • Malaria is caused by a protozoa parasite called plasmodium and its carrier is female anopheles mosquito, which is secondary host.

  • The liver is responsible for the detoxification of alcohol. Liver detoxify harmful substances through the complex chemical reactions.

  • Malaria is transmitted by the bite of female Anopheles mosquito while dengue is from female Aedes aegypti mosquito. Except this, Elephantiasis and yellow fever is also spread by mosquito.

  • Sir Ronald Ross, a doctor in Indian Army first observed oocysts of Plasmodium in the female. Anopheles won the Noble Prize in 1902 for his work on malaria.

  • Plasmodium vivax is a digenetic organism that completes its entire life cycle within two hosts human and female Anopheles and is a cause of malaria. It is a intracellular parasite in RBCs and live cells.

  • Platelets are rapidly decreased due to dengue fever. These are important to prevent more bleeding in body. So due to decreasing level of platelets the patient suffers from an excess of internal bleeding.

  • Yellow fever is contagious viral disease. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pain particularly in the back and headaches. The disease is caused by the yellow fever virus and is spread by the bite of the female mosquito “Aedese Aegypti”.

  • Plasmodium vivax is a protozoan parasite and a human pathogen, the most frequent and widely distributed causes of recurring malaria. P. vivax is one of the five species of malaria parasites that is responsible for 65% cases of malaria in India.

  • Meningitis is a disease caused by the inflammation of the protective membranes covering the brain and spinal cord known as meninges.

  • The femur is the longest bone in the human body. Vibrio cholera is the causing bacteria for cholera. The athletic foot is an infectious disease caused by Epidermophyton floccosum fungus.

  • The rotavirus is a group of RNA viruses, some of which cause a cute enteritis in humans. Rotavirus in the most common cause   of severe diarrhoea among infants and young children. It is a genus of double-stranded RNA virus in the family Reoviridae.

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  • Fear of water is known as hydrophobia. Such type of patients gets afraid from river, lake, sea etc. Hydrophobia is the old name of Rabies which is a viral disease. Its virus affects the nervous system.

  • Hysteria disease is mainly classed in young & unmarried women. It is a genital disease in which the symptoms of anxiety, discomfort, and faintness are found.

  • Silicosis is a lung disease that is caused by inhaling tiny bits of silica. Silica is a common mineral, which is part of sand, rock and mineral ores like quartz.

  • Potassium iodide (KI) is similar to food salt in the structure and physical properties. This commonly used in making iodised salt.  In addition potassium iodide, sodium iodide and sodium iodate are also used in making iodised salt.

  • Beri-Beri is refers to a cluster of symptoms caused primarily by a nutritional deficit in vitamin B1 (thiamine). Historically, beri-beri has been endemic in regions dependent on what is variously referred to as polished white or d-husked rice. This type of is responsible for beri-beri disease to lack of a primary source of thiamine.

  • The deficiency of iodine causes goitre in which the neck becomes thicker. Anemia is caused by iron deficiency. Vitamin A & B are useful to prevent night blindness and beri-beri respectively.

  • Magnetic resonance imaging (MRI) is a test that uses magnetic field and pulses or radio waver energy to make pictures or organs and structures inside the body.

  • BMD test is used for the diagnosis of osteoporosis. It is a disease of bones in which the chances of fracture increases. In this disease, the bone mineral density decreases and bone microstructure is destroyed.

  • A Salmonella in fection is a bacterial diseases of the intestinal tract. A salmonella is a group of bacteria that cause typhoid fever, food poisoning, gastroenteritis, enteric fever and other illness. People become infected mostly through contaminated water or foods.

  • Ergotism is a disease caused by consumption of contaminated grains. It is the effect of long-term ergot poisoning, traditionally due to the ingestion of the alkaloids produced by the Claviceps purpurea fungus that infects eye and other cereals.

  • Itai-Itai disease is caused by prolonged poisoning of cadmium. The first documented occurrence of mass cadmium poisoning in the world occurred in 1950 in Toyama Prefecture in Japan. However, for the first time, the disease was reported in 1912.

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  • Epidemic –        A large number of cases of a particular disease happening at the same time in a particular community.

  • Pandemic –        A human disease that spreads over the whole world or a large region of the world.

  • Endemic –        A disease  regularly found in a particular place or among a particular group of a people and difficult to get rid of.

  • Epizootic –        A disease that affects a large number of animals in some particular region within a short period of time.

  • DPT Vaccine refers to a class of combination vaccines against three infectious diseases in human: diphtheria, pertussis (A whooping cough) and tetanus. These are serious diseases caused by bacteria.

  • Phenylketonuria (PKU) is a disease caused by a metabolic disorder inherited as a recessive trait. The dominant gene “P”, in this case, codes for the enzyme, phenylalanine hydroxylase, formed in the liver cells. This enzyme catalyzes conversion of phenylalanine to tyrosine. In homozygous recessive genotypes, the absence of this enzyme causes a high level of phenylalanine in blood and tissues fluids. The phenotypic effects include a progressive mental retardation starting a few month after birth, seizures, and anomalies of teeth enamel and bones.

  • Common viral diseases include –

Chicken pox

Rabies

Flu (influenza)

Human immunodeficiency virus (HIV/AIDS)

Mumps, measles poliomyelitis etc

  • Acquired immune deficiency syndrome (HIV/AIDS) is caused by infection with the human immunodeficiency virus (HIV). HIV infects T-helper cells, a type of T-lymphocyte which helps both B –lymphocytes (which kill cells infected by viruses) to carry out their functions. Neither type of lymphocyte can therefore operate and so the body’s immune system is rendered infective, not only against HIV but to other infections also. Due to this reason AIDS victims are frequency killed within a few years of developing the disease.

  • Golden hour is the critical one-hour from the onset of a heart attack. Most of the death occur during this period if not treated properly.

  • Blue baby syndrome is an illness that begins when a large amount of nitrates in water are ingested by an infant and converted to nitrite by the digestive system. The nitrite them reacts with oxyhemoglobin to form methomoglobin, which cannot carry oxygen. If a large amount of methemoglobin is formed in the blood, body tissues may be deprived of oxygen, causing the infant to develop a blue coloration of their mucous membranes and possibly digestive and respiratory problems. This condition is also known as methemoglobinemia.

  • Bubble Baby Disease (severe combined immunodeficiency, SCID) if often called “bubble boy disease”. There are several forms of SCID. The famous “Bubble Baby Disease” is named so as the suffering baby is treated in a germ-free plastic bubble.

  • Beta-blockers, also known as beta-adrenoceptor blocking agents are drugs that are prescribed to treat different types of conditions, including hypertension (high blood pressure), angina, some abnormal heart rhythms, heart attack.

  • Potassium (K) plays a role in every heart beat. A hundred thousand times a day, it helps trigger the heart to squeeze blood through the body. It also helps your muscles to move, nerves work and kidneys to filter blood. Phosphorus is good for the development of bones whereas iron deficiency leads to anaemia.

  • ADH (Antidiuretic) hormone is released from pituitary gland which is responsible for controlling secretion of urine from kidney.

  • Arsenic-74 –        Tumour

Cobalt-60           –        Cancer

Iodine-131         –        Activity of thyroid gland

Sodium-24         –        Blood disorder

  • Gobalt-60 is a synthetic isotope of cobalt. Gamma rays are ejected after the bombing of neutrons on cobalt. This is the reason, why it is used in radiation treatment.

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  • Gold 198 (radioactive isotope) is used in the treatment of cancer.

  • Arsenic-74 tracer is used to detect the presence of tumour.

  • Sodium-24 tracer is used to detect the presence of blood clots.

  • Iodine-131 tracer is used to study the activity of the third gland.

  • Cobalt-60 is used to treat cancer

  • Carbon-14 is used to the date organic material.

  • Phosphorus-32 is used to control blood cancer (leukaemia)

  • Radio-Sodium is used to measure the speed of the blood flow in the human body.

  • Muscle dystrophy is a hereditary disease linked with X-chromosome which is derived by the execution of the ineffective genes present on X chromosome. This moves from generation to generation.

  • Radiation affects eyes the most and brain minimum.

  • Polio is a highly contagious viral infection that can lead to paralysis, breathing problems or even death. The term poliomyelitis is form the Greek polios meaning “grey”, myelos meaning the spinal cord. Poliomeyelitis is highly contagious via the faecal-oral (intestinal source) and the oral-oral (oropharyngeal source) routes. In endemic areas, wild polioviruses can infect virtually the entire human population.  The polio virus enters into the body through polluted food and water.

  • Alzheimer’s disease leads to nerve cell death and tissue loss throughout the brain. Over the time, the brain shrinks dramatically, affecting nearly all its functions.

  • Polio vaccine was discovered by Jones Salk in 1952. It is a dangerous disease in children which makes them handicapped. It is caused from polio virus which affects central nervous system (CNS).

  • Hepatitis-B one of is the most common serious liver infection in the world. It is caused by the hepatitis B virus (HBV) which attacks liver cells and can lead to cirrhosis, liver cancer or liver failure through contact with infected blood and bodily fluids that contain blood.

  • The Montoux Tuberculin Skin Test (TST) or the TB blood test can be used to test for tuberculosis infection. This test is performed by injecting a small amount of fluid called tuberculin into the skin in the lower part of the arm.

  • Khaira –        Zinc deficiency

Anaemia    –        Iron deficiency

Goitre        –        Iodine deficiency

Scurvy       –        Vitamin C deficiency

  • Tetanus is a bacterial disease caused by the bacteria Clostridium tetani. When the tetanus bacteria invade the body through a wound, they produce a toxin or poison, that causes muscles to become tight, which is very painful. Tetanus mainly affects the neck and abdomen. It is also known as “lock jaw” because if often causes a person’s neck and jaw muscles to lock, making it hard to open the month or swallow.

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  • Plague is a bacterial disease caused by Yersinia pestis, which primarily affects wild rodents. It is sprad from one rodent to another by fleas. Humans bitten by an infected flea usually develop a bubonic form of plague, which is characterized by a bubo i.e. a swelling of the lymph node draining the flea bite site. If the bacteria reach the lungs, the patient develops pneumonic plague. If diagnosed early, bubonic plague can be successfully treated with antibiotics. But in case of Pneumonic plague, patients can die within 24 hours after infection.

  • Minamata disease was first discovered in Minamata city in Kumamoto prefecture, Japan, in 1956. It was caused by the release of methyl mercury in the industrial wastewater from the Chisso Corporation’s chemical factory, which continued from 1932 to 1968. This highly toxic chemical bioaccumulated in shell fish and fish in Minamata Bay and the Shiranui Sea, which when eaten by the local people, resulted in mercury poisoning.

  • Scurvy is a rare condition that can develop if a person does not have enough vitamin C in his diet. The best way to prevent scurvy is to eat a healthy, balanced diet that contains plenty of fruit and vegetables. Foods rich in vitamin C will prevent scurvy- these include citrus fruits such as orange, grapefruit, lime and lemon and gooseberry (amla) and also includes many of non-citrus fruits such as papaya, strawberries, pineapple, kiwifruit, cantaloupe, and raspberries

  • The disease and affected part/organ:

Malaria               –        Blood cells

Filaria                 –        Lymph node

Encephalitis       –        Brain

Leukaemia         –        Bone marrow

  • Haemophilia –        Genetic disease

Diabetes             –        Hormonal disorder

Rickets               –        Deficiency disease

Ringworm          –        Fungal infection

  • By Air –        B.

By Water            –        Cholera

By Contract       –        Syphilis

By Wound          –        Tetanus

  • Malaria –        Protozoan

Poliomyelitis      –        Virus

Tuberculosis      –        Bacteria

Ringworm          –        Fungi

  • Our liver stores glycogen to fulfil body’s requirement of glucose for energy in between meals. This storage is recouped after every meal. If the meal is delayed further, the body starts consuming its fat reserve and proteins. This condition is starvation. Prolonged starvation causes Marasmus due to a generalized wasting of the body because of both energy and protein deficiency. Due to this, the body of children becomes lean and weak, eyes depressed and skin wrinkled.

  • The blank capsule used in dispensing are made of starch which melts easily in the stomach as a result medicine is reached in the body without disturbance.

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  • Tungro is a disease of rice found in South-East Asia. The cause of disease are two group of virus –

  1. RTSV: Rice Tungro Spherical Virus

  2. RTBV: Rice Tungro Bacilliform Virus

RTBC cannot be transmitted by leafhoppers unless RTSV is present but both are transmitted by green leaf hopper.

  • Blackheart is an abiotic disease which is caused due to low availability of oxygen during storage of potato.

  • Yellow vein mosaic disease okra is a viral disease. Bemisia tebkaci (whitefly) is a factor of this virus.

  • Karnal Bunt is a fungal disease caused by the smut fungus Tilletia Indica. It affects the quality of wheat. It was first reported in 1931, infecting wheat growing near the city of Karnal, Haryana.

  • White rust is a prominent fungal disease which spread is by fungi Albugo Candida. White lecions/patches appear on the stem, leaves & inflorescence of the plant, as a result the capacity of plant reduced. Fungicide should be used for the treatment of white rust.

  • Green hair disease is found in bajra. The symptom of green hair disease in the hairs of bajra becomes twisted. Green leaves and the hairs of bajra seems like a broom, as result the plants remains dwarf.

  • Pyrilla is leafhopper which sucks up leaves & plant sap of sugarcane. Under low infestation, yellow patches appear on the leaves that cause yellowintg & eventually drying of leaves. That’s why sugarcane crop growth disrupted. This insect is very harmful to sugarcane.

  • Powdery mildew is related with wheat, grape, barley, onion, apple & pear.

  • Ebola viruses are found in several African countries. Ebola was first discovered in 1976 near the Ebola River in what is now the Democratic Republic of the Congo. The name given to the viruses and the disease they cause is derived from the Ebola River.

  • H1, N1 is a flu virus. When it was first detected in 2009, it was called “swine flu” because the virus was similar to those found in pigs. Flu viruses have the ability to mutate quickly and pigs provide an excellent host for this. The H1N1 virus has developed the ability to spread among humans, who then infect each other through coughing and sneezing.

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  • Bird-Flu is the prevalent name of avian influenza which is caused by H5N1 virus. It is a contagious disease & affects mainly birds especially hens-cock & ducks. H5N1 can infect by two method –

  1. Directly hen to man contact

  2. Human to human transmission

Tamiflu is an anti-viral medication that blocks the actions of influenza virus types A and B.

  • Zika virus is primarily transmitted to people through the bite of an infected mosquito form the Aedes genus, mainly Aedes aegypti in tropical regions. This is the same mosquito that transmits dengue, Chikungunya and yellow fever. Sexual transmission of Zika virus is also possible.

  • In Coronary Artery Disease (CAD), the arteries that supply blood and oxygen to the heart muscle grow hardened and narrowed. In coronary artery bypass surgery creates a new path for blood to flow to the heat. The surgeon takes a healthy piece of vein from the leg or artery from the chest or wrist. Then the surgeon attaches it to the coronary artery, just above and below the narrowed area or blockage. This allows blood to bypass (get around) the blockage.

  • Aspirin also known as acetylsalicylic acid is a neurologically active drug which used to treat pain, fever and inflammation. Aspirin is also used long-term at low doses to help prevent heart attacks, stocks and blood clot formation in people. Aspirin belongs to non-narcotic analgesics.

  • Xerophthalmia is caused y severe Vitamin-A deficiency, is described by pathological dryness of conjunctiva and cornea. Cells of cornea get dried keratinized and vision power affected. That why Xerophthalmia should be prioritized.

  • During the heart attack, an internal way of blood vessels gets narrow due to a collection of cholesterol and rashes upon fibrous tissues and then reaching of blood clots makes the passage more narrow so the body gets less supply of oxygen and blood. The cause of heart attack may be obesity, hypertension, smoking and oily or fatty foods.

  • Emphysema is one of the several diseases known collectively as a chronic obstructive pulmonary disease (COPD) by which lungs of human gets affected.

  • Copper-T is an effective contraceptive and is one of the most immensely used methods of birth control worldwide. Although this method is very effective and widely used, it comes with some side effects also. Many women bleed between the menstrual cycle after the insertion of copper-T.

  • Diabetes develops when the body doesn’t make enough insulin or is not able to use insulin effectively, or both. Insulin is made in the pancreas, an organ located behind the stomach.

  • Two Canadian Scientists, Banting & Best prepared an active infusion of hormones insulin with help of Macleod in 1923. Banting & Macleod got Noble Prize (1923) for this scientific research. Insulin hormone is related to regulation of glucose in the blood.

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  • Interferons (IFNs) are a group of signalling proteins made and released by host cells in response to the presence of pathogens such as viruses, bacteria, parasites or tumour cells such as in cancer. Interferons (IFNs) alpha 2 is applied to cure the disease of blood cancer and kidney.

  • Leprosy is caused by a slow-growing type of bacteria called Mycobacterium leprae (M. leprae).

  • Thalassemia is a genetic blood disorder. In a patient of Thalassemia, the body is unable to synthesise enough haemoglobin, which causes severe anaemia.

  • Typhoid is caused by Salmonella typhi bacteria.

  • Gout is a disease caused by high level or uric acid in the blood (hyperuricemia). It causes an attack or sudden burning pain, stiffness and swelling in a joint.

  • Typhoid and Cholera are typical examples of waterborne diseases. Waterborne diseases are transmitted through water. The interruption of transmission is achieved by proper treatment of drinking water. Almost 4 million people die each year from water related diseases.

  • The vaccine of BCG should proculate just after the birth of baby to prevent T.B. However vaccine can be inoculated up to 12 months of age, but its decreases if inoculation getting late.

  • Edward Jenner, a legendary English physician and scientist are called “The father of immunology”. Jenner was the pioneer of smallpox vaccine, as his experiment opened the pathway of discovery of the immune system.

  • Smallpox is caused by variola virus which is a very infectious disease. It s transmitted from person to person via infective droplets during close contact with infected symptomatic people. The patient continuously suffers from fever and red rashes that appear on the skin. Smallpox vaccine is must for it and we should also be careful with clean surroundings.

  • Baldness is a fungal disease. AIDS is a fatal disease which affects the human immune system by HIV infection. Colour blindness is a genetic disorder.

  • Night blindness is a genetic disease. The cause of Night blindness is deficiency of Vitamin-A. Albunism is genetic disease in which the pigments called melanin is partially or completely absent in the skin, hair and eyes. Haemophilia is a genetic sex-linked disease. Colour blindness is also a genetic disease.

  • Jaundice, a yellowish pigmentation of the skin, the conjunctival membranes over the sclera and other muscous membranes caused by high blood bilirubin levels. This hyperbilirubinia subsequently causes increased levels of bilirubin in the extracellular fluid. Jaundice is often seen in liver diseases such as hepatitis or liver cancer. It may also indicate leptospirosis or obstruction of the biliary tract, for example by gallstones or pancreatic cancer.

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Genetic Engineering and Bio-Technology

  • DNA is a double helix with the sugar-phosphate backbone on the outside or the molecule. The bases are on the inside, oriented such that hydrogen bonds are formed between purines and pyrimidines on opposite chains. The pose pairing is very specific- A will always pair with T, G with C and the amount of adenine (A) is always equal to that of thymine (T) and the amount of guanine to that of cytosine. Because of this specific base pairing, the two stands of a DNA molecule are complementary (each stand contains all the information required to specify the sequences of bases on the other). Complementary base pairing between DNA strands makes it uniquely suited to store and transmit genetic information from generation to generation.

  • Sexual reproduction involves two present cells; each parent gives some of its traits (characteristics) to the offspring, Sexual reproduction causes genetic variation because of blending of genes, chromosomal change, shuffling of genes etc.

  • Vegetative or clonal propagation is an asexual reproduction in which successive mitosis of specialized vegetative propagules (as bulbs, corns, tubers, cuttings buds, and apomctic seeds) develop new plants and results in a clonal population. Viruses are transmitted from plant to plant in a number of ways such as vegetative propagation. Viral diseases could be transferred through vegetative parts.

  • Recombinant DNA Technology is used to cut a known DNA sequence from one organism introduce it into another organism thereby altering the genotype of the recipient.  Foreign DNA sequences can be introduced into bacteria, yeast, viruses, plant and animal cells.

  • New Science & Technology Policy-2003 was launched on 3, Jan 2003, for expanding new dimensions of innovation and preparation of futuristic perspective of science & technology, du ring 90th National Science Congress in Bengaluru. The policy includes optional utilisation of existing physical and knowledge resources, development of innovative technologies, Development of system and technologies for mitigation & management of natural hazards and management of intellectual property etc.

  • The world’s first buffalo calf through the “Hand guided Cloning Technique” was born on 6 February, 2009 at NDRI, Karnal and subsequently, the second cloned calf “GARIMA” was born on 6 June, 2009 with the birth weight of 43 kg.

  • Dolly was born in Roslin Institute of Scotland on July 5, 1996 by efforts of Ian Wilmut, Keith Campbell and his Colleagues. She was the first mammal in the world, cloned from adult somatic cell successfully. Dolly was developed by conventional cloning technique, not in vitro-fertilization. Vitro-fertilization is accepted widely for effective treatment of in fertility.

  • The team of scientists of NDRI situated in Karnal got success to develop a clone of buffalo, named as Garima II, Aug, 2010. Clone Buffalo Garima II gave birth a healthy female calf “Mahima: in NDRI on January 2013.

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  • The research group of National Taiwan University produced first transgenic glowing pig in 2006. Three male transgenic pigs were born by introducing glowing green protein in the embryo of pig.

  • World’s first female cloned camel named as Injaz developed in Camel Reproduction Centre, United Arab Emirates.

  • Through genetic engineering disease resistance, growth enhancement and animal cloning have been achieved successfully but human cloning has not got proper fruitful results because it is controversial and banned.

  • Treatment of different genetic disease, Alzheimer, Cystic, Fibrosis, myotonic dystrophy etc. can be possible with the help of DNA sequencing.

  • Somatic cell nuclear transfer (SCNT) can be used in embryonic stem cell research, or in regenerative medicine where it is sometimes referred to as “therapeutic cloning”. It can also be used as the first step in the process of reproductive cloning. The nucleus of the somatic cell is inserted into the enucleated (after removal of nucleus) egg cell.

  • World level programme “Human Genome Project” is related to identification and mapping of genes and its sequences.

  • Stem cells are undifferentiated biological cells that can differentiate into specialized cells and can divide (through mitosis) to produce more stem cells. They are found in multicellular organisms. There are three known accessible sources of autologous adult stem cells in human: Bone marrow, which requires extraction by harvesting that is drilling into bone (typically the femur or iliac crest).  This is an ultimate alternative to embryonic stem cells. Adipose tissues (lipid cells), which requires extraction by liposuction. Blood, which requires extraction through aphaeresis, wherein blood is drawn from the door (similar to a blood  donation) and passed through a machine that extracts the stem cells and returns other portions  of the blood to the donor.

  • Hybridoma technology is a technology of forming hybrid cell lines (called hybridomas) by fusing an antibody-producing B cell with a myeloma (B cell cancer) cell that is selected for its ability to grow in tissues culture and for an absence of antibody chain synthesis. The antibodies produced by the hybridoma are all of a single specificity and are therefore monoclonal antibodies (in contrast to polyclonal antibodies). The production of monoclonal antibodies was invented by Cesar Milstein and George J.F. Kohler in 1975.

  • The Plant field bank of Banthra will secure the endangered plants, prevent the piracy of biological diversity and also recognise the financial important plants.

  • Insect-resistant cotton plants have been genetically engineered by inserting a gene from a bacteria (Bacillus thuringiensis). Strains of Bacillus thuringiensis produces different toxins which are harmful to different insects. Such variety of cotton is commonly known as Bt. cotton. The American multinational company Monsanto has produced such variety.

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  • Brinjal is a transgenic brinjal created by inserting a gene “Cry 1 Ac” from the soil bacterium “Bacillus thuringiensis” into Brinjal. Bt. Brinjal has been developed to give resistance against lepidopteran insects like the brinjal fruit and shoot borer “Leucinodes orbonalis” and fruit borer Helicoverpa armigera. Bt. Brinjal has generated much debate in India.

  • Genome sequencing plays an important role in the agriculture sector. It can be used to identify genetic indicators, which is essential for developing properties such as disease resistant and dry tolerance in crops. It takes less time to develop new crops. Also, it is important to understand the host pathogen relationship in crops.

  • Cytoplasmic male sterility and gene silencing are techniques used to create transgenic crops. However, budding and grafting do not change the genetic structure of plants.

  • Biopesticides fall into three major classes: Microbial pesticides consist of a microorganism (e.g. a bacterium, fungus, virus or protozoan) as the active ingredient. Microbial pesticides can control many different kinds of pests, although each separate active ingredient is relativity specific for it target pests. For example, there are fungi that control certain weeds and other fungi that kill specific insects. Neem is the best example as biopesticides among flowering plants.

  • Terminator technology is the genetic modification of plants to make them produce sterile seeds. They are also known as suicide seeds. Terminator’s official name- used by the UN and scientists – is Genetic Use Restriction Technologies (GURTs). Although Terminator seeds are not yet being sold, in 2007 biotech companies with support of the US Department of Agriculture were conducting greenhouse tests for future commercialisation.

  • Generally Orobanche weed is found in a tobacco field. Orobanche weed is a parasitic weed which is found in tomato and potato fields also. It’s 150 species are spread over much of the world temperate and subtropical regions.

  • Golden rice is a variety of rice (Oryza sativa) produced through genetic engineering to biosynthesize beta-carotene, a precursor of vitamin A, in the edible parts of rice. The research was conducted with goal of producing a fortified fold to be grown and consumed in areas with a shortage of dietary vitamin A, a deficiency which is estimated to kill 670000 children under the age of 5 each year. A rice enriched with beta-carotene promises to boost the health of poor children around the world.

  • Golden rice was developed by Gurdev Singh Khush, a chief breeder at Philippines-based Rice Research Institute (IRRI). The research for super rice started in 1989. Gurdev Singh Khush is an agronomist and geneticist who along with mentor Henry Beachell, received the 1996 World Food Prize for his achievements in enlarging and improving the global supply of rice during a time of exponential population growth.

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  • Amniocentesis (also referred to as amniotic fluid test or AFT) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections and also used for sex determination in which a small amount of amniotic fluid, which contains fetal tissues is sampled from the amniotic sac surrounding a developing fetus and the fetal DNA is examined for genetic abnormalities.

  • A new way of mapping the “transcriptome” the collection of RNA read-outs that are expressed by a cell’s active genes has been devised by researchers. RNA is both the molecular bridge between DNA and the production of proteins that carry out the functions of like and the molecular toolbox that collectively helps those proteins do their work. As such, RNA exists in a variety of forms, each with a particular role and purpose, not all of which are fully understood.

  • Forensic DNA profiling (also called DNA testing or DNA typing) is a technique employed by forensic scientists to identify individuals b characteristics of their DNA. DNA profiling is used in for example parentage testing and criminal investigation. Samples taken for DNA testing in a criminal investigation can blood cells, bone cells, hair strands and saliva.

  • James Dewey Watson (born April 16, 1928) was an American molecular biologist, geneticist and zoologist, best known as one of the co-discoverers of the structure of DNA in 1953 with Francis Crick. Watson, Crick and Maurice Wilkins were awarded the 1962 Nobel Prize in Physiology or Medicine for their discoveries concerning the “molecular structure of nucleic acids and its significance for information transfer in living material”.

  • Geneco Technology is a technique for pre-information regarding genetic diseases such as prenatal investigation regarding the diseases in the fetus.

  • Industrial use of all organism, their substances or their biological process is known as Biotechnology. For example use of yeast cells for liquor production comes under Biotechnology.

  • Bio-magnification, also known as bio-amplification or biological magnification occurs when the concentration of a substance such as DDT or mercury in an organism exceeds the background concentration of the substance in its diet.

  • Such a process/technique will be known as hereditary engineering. By this method, not only the size of a creature can be changed or the quality can be changed but also a complete organism can be formed.

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  • DNA fingerprinting also called DNA typing, DNA profiling genetic fingerprinting, genotyping or identity testing in genetics, a method of isolating and identifying variable elements within the base-pair sequence of DNA (deoxyribonucleic acid). The technique was developed in 1984 by British geneticist Alec Jeffreys after he noticed that certain sequences of highly variable DNA (known as mini-satellites) which do not contribute to the functions of genes are repeated within genes.

  • Genetically modified crops (GMCs, GM crops, or biotech crops) are plants used in agriculture the DNA of which has been modified using genetic engineering techniques. In most cases, the aim to introduce a new trait to the plant which does not occur naturally in the species. Examples in food crops include resistance to certain pests, diseases or environmental conditions, reduction of spoilage or resistance to chemical treatments (e.g. resistance to a herbicide, to enable them to withstand drought, to increase the nutritive value of the produce to increase their shelf life, or improving the nutrient profile or the crop.

  • A new class of organic base fluorescent powders can be used for developing fingerprints on nonporous surfaces (e.g. plastics, poly bags, glass, metals etc.) multi-coloured and coloured glossy surfaces.

  • Metastalic cancer is cancer which spread from the place where it first started to another place in the body. The process by which cancer cells spread to other parts of the body is called metastasis. Cancer cell metastasis usually involves the following steps –

Local Invasion – Cancer cells invade nearby normal tissues.

Intravasation    – Cancer cells invade and move through the walls of nearby lymph vessels or blood vessels.

Circulation       – Cancer cells move through the lymphatic system and the bloodstream to other parts of the body.

Arrest and extravasation – Cancer cells arrest or stop moving in small blood vessels called capillaries at a distant location. Then invade the walls of the capillaries and migrate into surrounding tissues (extravasation).

Proliferation – Cancer cells multiply at the distant location to form small tumours known as micrometastases.

Angiogenesis – Micrometastases stimulate the growth of new blood vessels to obtain a blood supply. A blood supply is needed to obtain the oxygen and nutrients necessary for continued tumour growth.

Because cancers of the lymphatic system or the blood system are already present in lymph vessels lymph nodes or blood vessels, not all of these steps are needed for their metastasis.

  • In biology, a mutation is a permanent change of the nucleotide sequence of the genome of an organism, virus or extra-chromosomal DNA or other genetic elements, Mutations result from damage to DNA which is not repaired or to RNA genomes (typically caused by radiation or chemical mutagens), errors in the process of replication or from the insertion or deletion of segments of DNA by mobile genetic elements. Mutations play a part in both normal and abnormal biological processes including evolution, cancer and the development of the immune system including functional diversity and among living organisms, is the most responsible factor for bringing about the origin of a new species.

  • In biology, cloning is the process of producing similar population of genetically identical individuals that occur in nature when organisms such as bacteria, insects or plants reproduce asexually. Transgenesis is the process of introducing and exogenous gene- called a transgene- into a living organism so that the organism will exhibit a new property and transmit that property to its offspring. Transgenic bacteria are used to produce antibiotics on an industrial scale, new protein drugs and to metabolize petroleum products or plastics for cleaning up the environment. Transgenic animal are useful in basic research for determining gene function.

  • Pleiotrpy occurs when one gene influences multiple, seemingly unrelated phenotypic traits, an example being phenylketonuria, which is a human disease that affects multiple systems but is caused by one gene defect. Consequently, a mutation in pleiotropic gene may have an effect on some or all traits simultaneously. Other well-known examples of pleiotropy include albinism and sickle cell anaemia.

  • Gene therapy is an experimental technique that uses genes to treat or prevent disease. Gene therapy is the therapeutic delivery of nucleic acid polymers into a patient’s cells as a drug to treat disease. The polymers are either expressed as proteins, interfere with protein expression or possibly correct genetic mutations. The most common form uses DNA that encodes a functional, therapeutic gene to replace a mutated gene. The polymer molecule is packaged within a “vector”, which carries the molecules inside cells.

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Miscellaneous

  • Myoglobin is an iron and oxygen-binding protein found in the muscle tissues of vertebrates in general and in almost all mammals.

  • Dingoes are commonly found throughout Australia and in scattered groups across south-east Asia. Its scientific name is canis lupus dingo. Dingoes do not bark but howl like wolves.

  • “Red Ribbon Express” is a visual and moving medium to create and increase awareness about the means of transmission, prevention and perception of risk associated with HIV/AIDS.

  • Endoscopy means looking inside and typically refers to looking inside the body for medical reasons using an endoscope, an instrument used to examine the interior of a hollow organ or cavity of the body. Unlike most other medical imaging devices, endoscopes are inserted directly into the organ. By measuring the absorption of light by the blood (by passing the light through one fibre and collecting the light through another fibre) we can estimate the proportion of haemoglobin in the blood and diagnose unceration in the stomach. It works on the optical fibre which is based on the phenomenon called total internal reflection.

  • An X-ray computed tomography (X-ray CT) or computerized axial tomography scan (CAT scan), makes use of computer-processed combinations of many of X-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual slices) of specific areas of a scanned object, allowing the user to see inside the object without cutting.

  • Mission Indradhanush was launched by Ministry of Health and family Welfare (MOHFW) Government of India on 25th December, 2014. The objective of this mission is to ensure that all children under the age of two years as well as a pregnant woman are fully immunized against the seven vaccine preventable diseases.

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  • The Mission Indradhanush, depicting seven colours of the rainbow targets to immunize all children against seven vaccines preventable disease, namely –

  1. Diphteheria

  2. Pertussis

  3. Tetanus

  4. Tuberculosis

  5. Polio

  6. Hepatitis-B2

  7. Measles

  • Unsaturated fats include the two heart healthy choices-polyunsaturated and mono-unsaturated fats. Found primarily in fish, plant oils, seeds and nuts these “healthy” fasts have been shown to lower blood cholesterol levels and lesser risk of cardiovascular disease. Even though these fats are better than saturated and trans fats, they still have fats and intake should be moderate to maintain the good health.

  • HDL cholesterol is the well-behaved “good cholesterol”. This friendly scavenger cruises the blood stream. As it does it removes harmful had cholesterol from where it doesn’t belong. High HDL levels reduce the risk for heart disease – but low levels increase the risk. Trans-fat is generally considered to be bad for human health because it lowers the level HDL cholesterol.

  • Fatty alcohols are usually high molecular weight straight chain primary alcohols, derived from natural fats and oils. They are colourless, smellless and white crystalline substance and they are responsible for human heart disease. Sterols also known as steroid alcohols are subgroup of steroids they occur naturally in plant, animals and fungi with the most familiar type of animal sterol being cholesterol. Dietary intake of fatty acids daily in our food increase the cholesterol levels is the blood cells. These cells often become trapped in the walls of blood vessels (arteries) and contribute to atherosclerotic plaque formation.

  • Sunflower oil is known best for the heart patients. Sunflower is produced from oil type sunflower seeds. The oil is light in taste and appearance and provide more Vitamin E than any other vegetable oil. It contains monounsaturated and poly-unsaturated fats with low saturated fat levels. The U.S. Surgeon Journal reported “Eating less (saturated) fat is the most important change you can make to decrease your risk of heart disease”.

  • 1st December is celebrated every year as “World AIDS Day”. The international AIDS conference was held in Bangkok, the capital city of Thailand on 16 July, 2004. The main venue for the conference was to publish new guidelines underlining the effectiveness of anti-retroviral drugs to prevent the transmission of HIV from seropositive mothers to their child.

  • Laminaria is a brown algae commonly called “kelp”. Laminaria is a type of seaweed, native to Japan. Laminaria contains iodine. It is also a rich source of iron and potassium. Despite serious safety concerns about Laminaria, some people use Laminaria as medicine.

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  • Anti Leprosy Day          –        29/30 January (last Sunday in  January)

World TB day                      –        24 March

World Alzheimer’s day       –        21st September

World AIDS day                  –        1 December

World Environment Day     –        5 June

Teacher Day                        –        5 September

Food Day                             –        16 October

World Animal Day              –        3 October

World Minority Day            –        November 18

 Anit Leprosy  Day              –        31 January

International Ozone Day     –        16 September

  • Litmus is a water soluble mixture of different dyes extracted from lichens. It is often absorb onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity.

  • Skin Cancer               –        Ultraviolet Rays

Noise pollution           –        Decibel

Global warming          –        Carbon dioxide

Ozone hole                  –        Chloro-fluorocarbons

  • Saccharomyces is a genus of fungi that include many species of yeast. It used in fermentation of toddy.

  • Herbcides, also commonly known as weedkillers are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed.

  • Many yeasts such as the commonly used baker’s yeast Saccharomyces cerevisiae prefer fermentation respiration. These yeasts will produce ethanol under aerobic conditions if they are provided with right kind of nutrition.

  • A herbarium is a collection of preserved plants stored, catalogued and arranged systematically for study by professionals and amateurs from many walks of life. A collection like this is a vital reference when you need to indentify a plant and also serves to fix forever the identity of thousands of plant names.

  • Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in compact colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.

  • The Gharial, also known as Gavialis is a corcodillian of family Gavialidae mostly found in Ganga River. The large breeding population of gharial is found Bangladesh, Nepal and India.

  • World Diabetes Day (WDD) is celebrated every year on November 14.

  • The “Pongam Tree” is known as one of the richest and brightest trees of India. The tree is named as “Pongamia pinnata” in science. A red oil obtained from the seeds of the “Pongam Tree” can be used in embrocatng the skin diseases. It s used as bio-diesel as well.

  • India is the first biodiesel plant is established at Kakinada in Andhra Pradesh.

  • Cuscuta is a rootless, yellow coloured plant with a slender stem which twines around the host. It is an example of parasitic angiosperm. It develops haustoria which enter the host plant forming contact with xylem and phloem of the host. It absorbs the prepared food, water and minerals from the host plant.

  • Sugarcane ethanol is an alcohol-based fuel produced by the fermentation of sugarcane juice and molasses. Because it is a clean, affordable and low-carbon biofuel, sugarcane ethanol has emerged as a leading renewable fuel for the transportation sector.

  • Jatropha Curcas, the plant is considered a future feedstock for biodiesel production because it is easily grown in a harsh environment and is a non-edible crop. It is an Angiospermic plant. At the time of cultivation, it needs very less amount of water compared to other plants. The seeds of these plants are used as biodiesel. Biodiesel has become more attractive because of its environmental benefits and is obtained from renewable resources.

  • Pinus Gerardiana is the biological name of chilgoza pine. Chilgoza is rich in carbohydrate and protein and it is obtained from pine seeds.

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  • A pigment urochrome is the reason for the yellow colour of human urine. It is also known as urobilin.

  • Green plants are dependent on chlorophyll for photosynthesis and magnesium is required for chlorophyll production. In one of the crucial step in photosynthesis, light absorbed by chlorophyll excites electrons in the molecules, enabling them to be transferred to other molecules. Magnesium deficiency manifest itself in plants by yellowing of leaves between the veins.

  • Asiatic wild ass –        Equous hemionus

Barasingha                  –        Cervus duvauceli

Chinkara                     –        Gazella benneti

Nilgai                          –        Boselaphus tragocamelus

  • Crocodile is an endangered species.

  • Audiogram –        Ear

ECG                            –        Heart

EEG                   –        Brain

Mammogram     –        Breast

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  • EEG –        Electroencephalography is a process related to the brain in which the electrical activities are recorded by the bombarding of neutrons.

  • ECG –        Electrocardiography is the process of the recording of heart’s electrical activities.

  • EOG –        Electrooculography is the technique of measuring the resting power of retina.

  • EMG –        Electromyography is a test in which the veins of muscles are checked.

  • Hydra has no blood but respires. Bothe the gaseous exchange and excretion occur by simple diffusion.

  • Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous relatively abrupt change in the animal’s body structure through cell growth and differentiation. Thyroid hormone controls remodelling of the tadpole intestine during the climax of amphibian metamorphosis. During the metamorphosis of frog, intestine shortens in length which helps to digest flesh food.

  • A hyperparasite is a parasite whose host is a parasite. This form of parasitism of especially common among entomophagous parasite. The term is used loosely to refer also to parasitoids whose hosts are parasites or parasitoids; the distinction is not always clear or interest in practice.

  • Mycoplasma is the smallest organism, capable of autonomous growth and reproduction.

  • Xylem is composed of dead cells, while phloem is made up of living cells. Phloem transports food from the leaves to the rest of the plant body.

  • Bull semen for the purpose of artificial insemination is stored i – 1960 C in liquid nitrogen.

  • The photo receptor cells in human eye are most sensitive to colours between the wavelength of 530-535 nanometer. The sensitivity of our eyes is most for yellow and green colour.

  • Holstein-Friesians are a breed of cattle known as the world’s highest-production dairy animals. They are mainly originating Netherlands. They are farmed for their large dairy production averaging 23285 pounds of milk per year.

  • Concave mirrors are used by dentists because at a short range (object distances less than the focal length) they produce magnified, upright images. It is useful to have a magnified image of a tooth when you’re looking for or repairing cavities, cracks or other abnormalities.

  • Myoglobin –        Muscle cell

Sarpgandha        –        Tranquilizer

Carcinoma         –        Radiotherapy

Haemoglobin     –        Oxygen transport

  • Bulimia –        Eating disorder

Cholesterol        –        Egg-Yolk

Atropine             –        Alkaloid

Insulin                –        Pancreas

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  • Amphibians and most reptiles have a heart with three chambers-two atria and a single ventricle. The heart of the frog has three chambers, one ventricle and two atria.

  • An electric diode using a semiconductor nanoparticle material synthesised by microorganisms has been recently fabricated by Indian scientists for the first time with by the help with of yeast Schizosaccharomyces pombe having utility in device miniaturization. The diode was created by using this cadmium sulphate with phenylene vinylene. The organism used during this process Schizosaccharomyses pombe.

  • Specialist Body Part

Cardiologist       –        Heart

Nephrologist      –        Kidney

Urologist            –        Urinary tract

Oculist               –        Eye

  • Anaesthetic substances are mainly used for decreasing the feelings. William Mortan has used it for the first time in 1846 in the form of di-ethyl ether. In 1847, Jams Sampson used chloroform as an anaesthetic. Chloroform, Nitrous oxide, pentothal sodium, hailothen, chloropropane cocaine are used as an anesthetic.

  • Laika was a Soviet space dog who become one of the first animals in space and the first animal to orbit the earth. Laika, a stray dog from the streets of Moscow, was selected to be the occupant of the Soviet spacecraft Sputnik 2 that was launched into outer space on November 3, 1957.

  • Particulate matter (PM) also known as particle pollution, is a complex mixture of extremely small particles and liquid droplets that get into the air. Once inhaled, these particles can affect the heart and lungs and cause serious health problems.

  • Neurology is a branch of medicine dealing with disorders of the nervous system. Cardiology is a branch of medicine dealing with the disorders of the heart as well as parts of the circulatory system. Gastroenterology is the branch of medicine focused on the digestive system and its disorders. Urology is the branch of medicine that focuses on surgical and medical diseases of the male and female urinary tract system and male reproductive organs.

  • Colostrum has been marked as a safe dietary supplement by the International Olympic committee and it can be used as performance enhancing substance by the athletes.

  • Angora wool is obtained from a breed of rabbit or goat.

  • Termites are also known as white ants.

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  • The chief mosquito repellent is obtained from neem. Neem has medical quality, medicines are prepared by its seeds & leaves. Basil & turmeric have the antibiotic quality. Lemon is the main source of Vitamin C.

  • Ultrasonic is a technique for monitoring foetal growth. It is the application of ultrasound. Ultrasound can used for medical imaging, detection, measurement and cleaning. At higher power levels, ultrasonic is useful for changing the chemical properties of substances.

  • Indian veterinary Research Institute or IVRI is located at Izzatnagar, Bareilly in Uttar Pradesh. It is India’s premier advanced research facility in the field of veterinary medicine and allied branches.

  • CDRI (Central Drug Research Institute) is located in Lucknow.

  • AIDS program, Sanraksha (Bengaluru) was started as an HIV counselling services in 1993 and today offers a continuum of services that range from HIV testing to hospice care.

  • The Survey of India is India’s engineering agencies in charge of mapping and surveying. It was set up in 1767 and has evolved rich traditions over the years. Survey of India functions under the Ministry of Science and Technology.

  • The Headquarters of Survey of India is located in Dehradun.

  • The National AIDS Control Organisation (NACO), established in 1992, is a division of India’s Ministry of Health and Family Welfare that provides leadership of HIV/AIDS control program in India through 35 HIV/AIDS Prevention and Control Societies and is “the nodal organisation for formulation of policy and implementation of programs for prevention and control of HIV/AIDS in India.

  • Central Electrochemical Research Institute is one of a chain of forty national laboratories under the aegis of the Council of Scientific and Industrial Research (CSIR) in New Delhi. founded on July 25, 1948 at Karaikudi in Tamil Nadu.

  • High Security Animal Disease Laboratory is located at Bhopal, Madhya Pradesh.

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  • Central Drug Institute                                     –        Lucknow

Central Leprosy Institute                                         –        Agra

Motilal Nehru National Institute of Technology        –        Allahabad

Indian Institute of Sugar Technology                     –        Kanpur

The central Institute of medicinal and Aromatic Plants        –        Lucknow

Centre for DNA finger Printing and Diagnostics                 –        Hyderabad

Institute of Microbial Technology                           –        Chandigarh

National Institute of Immunology                           –        New Delhi

F.A.O. Headquarters                                                –        Rome

Central Agmark Laboratory                                    –        Nagpur

Central Rice Research Institute                               –        Cuttack

Central Potato Research Institute                            –        Shimla

  • Birbal Sahni Institute of Palaeobotany (acronym BSIP) is an autonomous institute or non C.S.I.R. Institute constituted under the Department of Science and Technology, Government of India. The Institute is located at Lucknow, Uttar Pradesh and is a place of higher learning in the field of plant fossil research.

  • The National Institute for the mentally Handicapped is situated at Hyderabad.

  • The National Bureau of Plant Genetic Resources (NBPGR) has its headquarters at New Delhi.

  • Testosterone –        Hormone

Codeine              –        Sedative drug

Caoutchouc        –        Rubber source substance

Eugenol              –        Aromatic oil of chouc

  • The National Botanical Research Institute (NBRI) is a research institute of CSIR in Lucknow. It engaged in the field of taxonomy and modern biology.

  • The largest brain belongs to the sperm whale: 7 kg (17.5 pounds). The blue whale, the largest animal on the planet, being twice longer and thrice heavier, has a brain weighing 5 kg (12.5 pounds).

  • Human brain has an average weight of 2.7 pounds (1.2 kg), variation between 1.1 and 1.4 kg being considered normal. Our brain represents 2% of our weight, the largest brain in the animal world compared to the body size.

  • The largest brain of terrestrial animal is that of elephant 10.5 pounds (4.78 kg). Still, the brain of the elephant makes less than 0.1% of its body weight.

  • Ant has the largest brain in proportion to its body size.

  • Avahan is an initiative sponsored by the Bill & Melinda Gates Foundation to reduce the spread of HIV in India. It began in 2003.

  • The first dianosaurian has been opened in Hyderabad. This dianosaurian has been opened in B.M. Birla Science center in Hyderabad.

  • WHO (World Health Organization) headquarters is located in Geneva.

  • The first Dental College of the country was founded in 1924 in Kolkata. Its name was R. Ahmed Dental College.

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  • The bear which we see commonly performing on streets in Sloth Bear.

  • Anthrax –        A toxin used by biowarfare

Thalassemia       –        Disease due to a defective gene

Surrogacy           –        Womb-renting

Transgenics        –        A science of altering genomes

  • Shark fish contains no bones in its body. Sharks and other cartilaginous fish (skates and rays) have skeletons made of cartilage and connective tissues.

  • Bees are the member of genus Apis. They fly on the average speed 15 miles/hour (21 kmph) while their speed in returning with food is approx 12 miles/hour (17 kmph).

  • A polytunnel (also known as s polyhouse, hoop greenhouse or hoop house or high tunnel) is a tunnel made of polyethylene, usually semi-circular, square or elongated in shape. These poly houses are used in agriculture for growing plants. It products crops form the bright sun, hails, storms etc.

  • Cocoa is a non-alcoholic beverage which is obtained from Cacao plant (Theobroma cacao), which belongs to family Sterculiaceae. The roasted cocoa beans contain fat which is known as cocoa butter (30-56%), starch (15%), albuminoids (15%) and mineral matter. The stimulating qualities are due to the presence of theobronine (3.0%) and small a quantity of caffeine.

  • Caffeine is a naturally occurring compound found in the leaves and fruits of certain plants. It is found in coffee, tea, cocoa, cola, soft drinks. As a stimulant, caffeine acts on the brain and nervous system. In small doses, it can make anyone feel refreshed and focused. While in large doses, likely to feel anxious and have difficult in sleeping.

  • Silica get s most commonly encountered in everyday life as beads in a small (typically 2*3 cm) paper packet. In this form, it is used as a desiccant to control local humidity to avoid spoilage or degradation of some goods. Because silica gel can have added chemical indicators and absorbs moisture very well, silica gel packets usually bear warnings for the user not to eat the contents. It is mainly used for the packed medicines.

  • STUDY FOR CIVIL SERVICE – GYAN

 

  • Shanti Swaroop Bhatnagar was a well-known Indian scientist, a professor of chemistry for over 19 years. He was the first director-general of the Council of Scientific and Industrial Research (CSIR), and he is revered as the “father of research laboratories”. He was also the first Chairman of the University Grants Commission (UGC). To honour his name and achievements, CSIR instituted an award Shanti Swarup Bhatnagar Prize for Science and Technology, since 1958 for outstanding scientists who made significant contributions in various branches of science.

  • Ligases, work as molecular stitchers are the class of enzymes that catalyze the formation of covalent bonds and are important in the synthesis of biological molecules such as DNA etc. Ligase also activates the process of repair in the break up biological molecules by catalysing the formation of bonds (covalent bonds) between the broken up fragments. Therefore ligases can be given the name of molecular stitchers.

  • Peppermint oil or menthol oil is made up of peppermint leaves by steam distillation process. Its scientific name is Mentha arrensis. The oil has a high concentration of natural pesticides. The mainly constitutes menthol (40.7%) and menthone (23.4%).

  • Saffron is spice derived from the flower of Crocus sativus, commonly known as the “saffron crocus”. Saffron crocus grows to 20-30 cm (8-12 in) and bears up to four flowers, each with three vivid crimson stigmas, which are the distal end of a carpel. The styles and stigmas, called threads are collected and dried to be used mainly as a seasoning and colouring agent in food. Saffron is among the world’s most costly spices by weight.

  • The antibody also called immunoglobulin a protective protein produced by the immune system which fights against the infection from pathogens such as bacteria and viruses. Antibodies are produced by specialized white blood cells called b-lymphocytes (or B cells).

  • Kuttu flour is obtained from the plan of Buckwheat (Fagopyrum esculentum). This plant is cultivated for its grain-like seeds and also used s a cover crop. Despite the name, buckwheat is not related to wheat, as it is not a grass. Instead, buckwheat is related to sorrel, knotweed and rhubarb. Because its seeds are eaten, it is referred to as a pseudocereal.

  • Barium is a good absorber of x-rays and this helps the stomach to appear clearly in contrast with the other regions in the picture. So it’s suitable form is administered to patients before an X-ray examination of the stomach. It is used to diagnose abnormalities of the gastrointestinal tract, such as tumours, ulcers etc.

  • Gambusia is the large genus of fish in family Poecilidae (order Cyprinodontiformes). The release of Gambusia into ponds and wells helps in controlling the mosquitoes. Gambusia is known for controlling mosquito populations or mosquito borne diseases. Gambusia fish is 3-5 cm overall of length size, who eats the mosquitoes larva and egg, which helps in controlling the mosquitoes disease like dengue and malaria.

  • STUDY FOR CIVIL SERVICE – GYAN

 

  • Hybrid seed is changed every year. In agriculture and gardening hybrid seed is seed produced by cross pollinated plants. Hybrid seed production is predominant in agriculture and home gardening.

  • Technically flowers are modified stems with modified leaves. Thus flowers do not come from leaves, but from younger parts of growing stems. Apart from light and chemical stimulus for flowering, temperature is also one important stimulus that a lot of plant species use to flower, e.g. some orchid species.

  • The first dwarf variety of rice developed in India was Jaya.

  • Crop-logging may be great help to determine the adequate levels of different nutrients for good plant growth and high yield. The concept of crop-logging was developed by Clements of USA for the growing of sugarcane in Hawaii, where the fertilizer requirements of this crop are greatly influenced by weather and climate. Crop logging is a method of plant analysis for assessing the requirement of nutrients for crop production.

  • The weedicide commonly used for paddy is 2, 4-D (2, 4-Dichlorophenoxy Acetic Acid). Its chemical formula is C8H6Cl2O3. It is selective translocated herbicide and most widely used to control broadleaf weeds.

  • “Dapog” method of raising rice nursery was developed in Philippines. It has been introduced in India from Philippines. The main merit of this method is that less area is needed to raise seedings. Twenty-five to 30 square meters of the area is enough to raise seedings sufficient for planting one hectare.

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  • Green Revolution –        Food grains

  • White Revolution      –        Milk and milk products

  • Yellow Revolution –        Oil seeds

  • Blue Revolution –        Fish and aquaculture

  • Bioluminescence is light produced by a chemical reaction with in a village organism. The chemical reaction that results in bioluminescence requires two unique chemicals: luciferin and either luciferase or photoprotein. Luciferin is the compound that actually produces light. Most bioluminescent organisms are found in the ocean. These bioluminescent marine species include fish, bacteria and jellies. Phosphorescence is a process in which energy that is absorbed by a substance is released relatively slowly in the form of light.

  • Phytotron is a technique of self-contained hydroponic grow box in which plant is grown at high yeild full size when it stops growing.

  • Liver fluke is a common endoparasite in the larger bile ducts and passage of the liver of sheep and hence commonly called “sheep liver fluke”. It can also develop in horses, pig, goats etc. Mammals are its primary host and snail is its secondary or intermediate host.

  • STUDY FOR CIVIL SERVICE – GYAN

  • STUDY FOR CIVIL SERVICE – GYAN

  • STUDY FOR CIVIL SERVICE – GYAN

 

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