Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

Write a brief note on the work of Walter Sutton and Theodore Boveri?

The genetically-modified (GM) brinjal in India has been developed for:

1. Insect-resistance.
2. Enhancing shelf life.
3. Enhancing mineral content.
4. Drought-resistance.

Who developed the technique of electrophoresis? Write the principle on which it is based.

Two statements are given-one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.

1. Both assertion and reason are true and reason is the correct explanation of assertion.
2. Both assertion and reason are true but reason is not the correct explanation of assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Organs of pig such as heart, pancreas, etc., for human use can be grown through transgenic animals.
Reason: Transgenic pigs show improved growth and meat production.

Mention the pollinating agent of an inflorescence of small dull coloured flowers with well exposed stamens and large feathery stigma. Give any one characteristic of pollen grains produced by such flowers.

Define climax community.

Name two parasitic species of plants that produce many minute seeds in a fruit.

What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for year answer?

State the consequence, if IMR will increase and MMR will decrease in a population.

Name the earliest fossil of pre-historic man.