Introduction to Biology

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Biology is the branch of science to study about living beings.

It is important to study biology for many reasons. some the main importance s of studying biology is described below. 

1. Understanding about  biological diversity 

Biology makes us understand that we are only a small part of this living planet.

Thereare around 30 million species of animals and plants in the world. The relationship between living and non living world is a dynamic one.

2. Understanding about  the human body and its functions

study of biology helps us to understand the structure and function of the human body thereby helps us to fight against ailments, cure the diseases and improve the quality of life.

3. Managing  natural resources and environment:

biology deals with the studies on management and conservation of nature and its resources. It warns us about the possible environmental hazards such as ozone depletion, deforestation etc.

4. Sustainable food production:

Since all our food comes from plants and animals, we must find ways to improve the food production by developing agronomy, microbiology, food production etc. It is said that the  current human population of 6 billion and it is expected to double in less than 40 years. Therefore sustainable food production is necessary.

5. Understanding about  causes , effects and cure  of diseases:

Diseases such as cancer , AIDS, malaria  polio and other epidemics can be controlled by the concerted effots of biologists. systematic knowledge of botany can help to discover unknown medicinal plants. understanding of hereditary diseases , a biologist can do genetic counselling. 

Atmosphere And Environment

life on earth would not survive without air and water. According to the survays done by scientists over the years the composition and the state of air and water is changing rapidly in an alarming rate which might result in many adverse effects. In order to maintain the optimum composition of air and water, it is necessary to have an overall idea of the atmospheric and water pollutants, their sources, problems caused by them and most importantly the steps we can take to minimize these effects.

Composition of gases present in dry air by volume

78% nitrogen
21% oxygen
0.04% Carbon dioxide
0.96% argon and other noble gases


In order to obtain the gases separately, atmospheric air is the best resource. As different gases has significantly different boiling points, they can be separated by fractional distillation of liquid air.

water from natural sources contains a variety of dissolved substances shown below

Naturally occurring substances

• mineral salts
•  oxygen
• organic matter

Pollutant substances

•  metal compounds
•  sewage
•  nitrates from fertilisers
•  phosphates from fertilisers
• detergents
• harmful microbes

Next about air pollutants