Ecosystems — BIOLOGY STD 12 Science — Question

Differentiate between geitonogamy and xenogamy in plants. Which one between the two will lead to inbreeding depression and why?

How is diapause different from hibernation?

2, 4-D is used as herbicide.

1. List the two methodologies which were involved in human genome project. Mention how they were used.
2. Expand ‘YAC’ and mention what was it used for.

What is sewage? Describe its composition

Since October 02, 2014 'Swachh Bharat Abhiyan' has been launched in our country.

1. Write your views on this initiative giving justification.
2. As a biologist name two problems that you may face while implementing the programme in your locality.
3. Suggest two remedial methods to overcome these problems.

Explain types of enzymes used in biotechnology?

Sapna's younger brother saw a banana tree in backyard of a house. He could see the fruits but no seeds.
He wanted to know how a new plant will be produced without seed and asked Sapna (a class XII biology student) about it. She explained that some plants can grow without seeds and the phenomenon is called vegetative propagation. Her brother was amazed to know the new concept about plants.

1. How does banana produce a new plant? Is this reproduction, sexual or asexual?
2. Give examples of some other fruits and vegetables that can reproduce by this method.
3. Identify the values shown by Sapna's brother.

What are 'cloning sites' in a cloning vector? Explain their role. Name any two sites in pBR 322.

Blood plasma.