Organisms and Populations — BIOLOGY STD 12 Science — Question

Processing of hnRNA.

Naman entered into a quarrel with some farmers who were spraying DDT in their field. Many people gathered at the spot to see and enjoy the incident. The angry mob demanded that Naman should not interfere in the farmer's job. Naman tried to explain his point and finally succeeded in explaining the harmful effects of DDT.

1. What is biomagnification? Explain with an example.
2. Is biomagnification related with DDT only? Comment.
3. What is the effect of DDT on birds?
4. What values did Naman promote?

Study the schematic representation of the genes involved in the lac operon given below and answer the questions that follow.

1. Identify and name the regulatory gene in this operon. Explain its role in 'switching off the operon.
2. Why is lac operon's regulation referred to as negative regulation?
3. Name the inducer molecule and the products of the genes 'z' and 'y of the operon. Write the function of these gene products.

How Indian culture and traditions helped in bio-diversity conservation? Give importance of conservation in terms of utilitarian reasons.

Give the central dogma of protein synthesis. Explain the process of translation.

What are the different types of reflexes?

1. Why are engineered vectors preferred?
2. A vector is engineered with three features, which facilitate its cloning within the host cell. List the three features and explain each one of them.

Euchromatin and Heterochromatin.

What is organic farming? Discuss the benefits of organic farming as a viable practise in the context of developing nations like India.

Industrial uses of enzymes.