Life Sciences Glossary: From Chromosphere to Chemotherapy and Chickenpox

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Rarified layers of gases surrounding the Sun lying outside the photosphere but inside the corona.


Heavenly body within the gravitational field of the Sun, which is occasionally visible to the naked eye, its three parts are the nucleus, which is very bright, the coma, nebulous patch of light surrounding the nucleus and the tail which has a faint haze of light.

Communication Satellite

A satellite which is equipped to act as a middle relay station for a transmitting and receiving station pair, thousands of miles apart.

Concave Mirror

Normally forms a real and inverted images of an object. The image is virtual, erect and enlarged when the object is close to the mirror at a distance less than its focal length. In this position, it can be used as a shaving mirror.

Carbon Monoxide

Is the most common pollutant of air in an urban atmosphere?


The action of a catalyst or substance in changing the rate of a chemical action without its own participation in the reaction.


The act of coagulating or precipitating colloidal particles by either addition of an electrolyte or warming it. Coagulation of the muddy water of river is done by the addition of alum.

Caustic Soda

(Sodium hydroxide) is used in soap manufacture.


  • Is used to purify water in cities for human consumption.
  • D. D. T (Dichloride Biphenyl Tricolor ethane) is a contact insecticide. It has a pungent smell.

Common Chemicals and Their Chemical Names

Common Chemicals and Their Chemical Names
Baking powderSodium bicarbonate
Common saltSodium chloride
Caustic sodaSodium hydroxide
Gluer՚s saltSodium Sulphide
Water glassSodium silicate
Plaster of ParisPowdered calcium Sulphide
PotassiumPermanganate of potash


Sodium thiosulphate (used as a fixer in Photography)
Niter, saltpeterPotassium nitrate (used in gun powder)
Lunar causticSilver nitrate
Quick limeCalcium oxide
Bones ashCalcium phosphate (Used as a fertilizer)
Wood՚s metalBismuth, lead and cadmium
Yellow brassCopper and zinc


It is the process of transmission of heat in which energy is handed over from one particle to another.


Are substance through which an electric current flows easily? Usually, metals are good electrical conductors, whereas non- metals are not. Silver is the best electrical conductor, Copper, Aluminum and mercury are other examples. Wood, plastic, asbestos etc. are examples of non- conductors or insulators.

Convex Lens

Converges a beam of light to a point when it passes through it. It normally gives a real, inverted image. It is used as a magnifying glass, when held close to an object.

Convex Mirror

Forms a virtual erect and a diminished image of an object. It is used by motorists to get a view of the traffic coming from behind.

Cosmic Rays

High energy particles and electromagnetic radiations which originate from outside the Earth՚s atmosphere.

Cosmic Year

Is the time taken by the Sun center of the galaxy, i.e.. 250 million years?

Critical Temperature

Is the temperature above which a substance can exist only in its gaseous state and cannot be liquefied regardless of the magnitude of pressure exerted on it?


A mucopolysaccharide, the chief ingredient in mucus.


A sense organ of aquatic animals that responds to water current.


A disorder of lips and mouth characterized by scales and fissures resulting from the deficiency of riboflavin.


The treatment of illness or disease by chemicals/pharmaceuticals.


An acute highly contagious viral disease caused by a herpes virus, Varicella zoster virus, primarily in young children.

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