Human Reproduction — BIOLOGY STD 12 Science — Question

“Pollen grains in wheat are shed at 3-celled stage while in peas they are shed at 2-celled stage.” Explain. Where are germ pores present in a pollen grain?

Name the source of statin and state its action on the human body.

OR

Name a microbe used for statin production. How do statin lower blood cholesterol level?

For producing a recombinant protein (for therapeutic purpose) in large scale, which vector would you choose—a low copy number or high-copy number?

How does addition of a small amount of curd to fresh milk help in the formation of curd? Mention a nutritional quality that gets added to the curd.

OR

How does ‘starter’ added to milk help it to set into curd?

State how has Agrobacterium tumifaciens been made a useful cloning vector to transfer DNA to plant cells.

When does ovulation occur?

Write a short note on male accessory glands.

Name two basic types of competition found amongst organisms. Which one of them is more intense and why?

Uses of Microbes in household Products(Any Tow)

Give an account of two modern technology who are pioneer to biotechnology.