Organisms and Populations — BIOLOGY STD 12 Science — Question

Insulin in the human body is secreted by pancreas as prohormone/ proinsulin. The schematic polypetide structure of proinsulin is given below. This proinsulin needs to undergo processing before it becomes functional in the body. Answer the questions that follow:

1. State the change the proinsulin undegoes at the time of its processing to become functional.
2. Name the technique the American company Eli Lilly used for the commercial production of human insulin.
3. How are the two polypeptides of a functional insulin chemically held together?

Name the blank spaces a, b, c and d given in the following table:

Type of microbe	Name	Commercial product
Bacterium	a	Lactic acid
Fungus	b	Cyclosporin A
c	Monascus purpureus	Statins
Fungus	Penicillium notatum	d

Define pollination. Describe briefly about pollination in vallisnaria and sea grass.

How do homogametes differ from heterogametes? Give an example of an organism for each of the two kinds.

Branching descent and natural selection are the two key concepts of Darwinian Theory of Evolution. Explain each concept with the help of a suitable example.

How arein-situ and ex-situ approaches of biodiversity conservations different from each other?

The diversity of plants and animals is not uniform throughout the world but shows a rather uneven distribution. Explain with example.

Both a wine maker and a molecular biologist who had developed a recombinant vaccine claim to be biotechnologists. Who in your opinion is correct?

How is pollination carried out in water plants?

1. Which stage of Entamoeba histolytica is pathogen to humans?
2. Why E. histolytica does not have contractile vacuole?
3. Which form of E. histolytica serves for transmission of the parasite?