Reproduction in Lower and Higher Plants — 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?

Community service department of your school plans a visit to a slum area near the school with an objective to educate the slum dwellers with respect to health and hygiene.

1. Why is there a need to organise such visits?
2. Write the steps you will highlight as a member of this department, in your interactions with them to enable them to lead a healthy life.

Antigen and antibody.

State any three benefits of mycorrhiza.

In normal human heart, there is no mixing of oxygenated and deoxygenated blood.

Enlist the steps involved in inbreeding of cattle. Suggest two disadvantages of this practice.

There are certain complexities in eukaryotic transcription. Bring out the significance of such complexities.

Answer the following questions:
Describe the endosperm development in coconut.

Give Reasons: Initially proteins (and not DNA) were considered as genetic material.