Science (English Medium) Class 12 - CBSE Question Bank Solutions for Biology

Describe one example of adaptive radiation.

Do you think microbes can also be used as a source of energy? If yes, how?

Common detritivores in our ecosystem are ______.

The major reservoir of carbon on earth is ______.

Distinguish between production and decomposition.

Define decomposition.

What are the major causes of species losses in a geographical region?

Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?

What are the various constituents of domestic sewage?

Write the steps you would suggest to be undertaken to obtain a foreign-gene-product.

Public all over India is very much concerned about the deteriorating air quality in large parts of North India. Alarmed by this situation the Resident’s Welfare Association of your locality organized an awareness programme entitled “Bury not burn”. They invited you, being a biology student to participate.

1. How would you justify your arguments that promote burying and discourage burning? (Give two reasons)
2. With the help of flow charts, one for each practice depict the chain of events that follow.

How do mycorrhizae help the plants to grow better?  

Mention any four special adaptive evolved in parasites for their parasite mode of life.

How do methanogens help to generate biogas?

State the role of “biolistic gun” in biotechnology experiments.

Explain the roles of the following with the help of an example each in recombinant DNA technology :

Plasmids

Name the animals in which methanogens occur and the role they play there.

Why has the Indian Government set up the organisation named GEAC ? Give any two reasons.

Why should a bacterium be made ‘competent’ ?

Explain the role of ‘microinjection’ and ‘gene gun’ in biotechnology