Organisms and Populations — BIOLOGY STD 12 Science — Question

Why should a bisexual flower be emasculated and bagged prior to artificial pollination?

Define spermiogenesis. Where does it occur?

What is a disease? which groups are diseases classified into? Explain with example.

After a brief medical examination a healthy couple came to know that both of them are unable to produce functional gametes and should look for an ‘ART’ (Assisted Reproductive Technique). Name the ‘ART’ and the procedure involved that you can suggest to them to help them bear a child.

If the length of E.coli DNA is 1.36mm, calculate the number of base pairs in E.coli.

Is the use of contraceptives justified ? Give reasons.

List the three hormones produced in woman only during pregnancy. What happens to the levels of estrogen and progesterone during pregnancy.

If abiotic origin of life is in progress on a planet other than earth, what should be the condition there? Explain.

Name the group of cells the HIV enters after getting into the human body. What happens in these cells and what are these cells subsequently referred to as? Name the next group of cells the HIV attacks from here.

Name the process of the rupture of Graafian follicle and the subsequent release of the egg from the ovary.