Human Reproduction — BIOLOGY STD 12 Science — Question

Draw a well-labelled diagram of an antibody molecule.

You have chosen a plasmid as vector for cloning your gene. However this vector plasmid lacks a selectable marker. How would it affect your experiment?

Fed up of a large family, a couple wanted to adopt a terminal method of contraception. Describe the process conducted by the doctor in either of the cases (male/female partner).

Match Column I with Column II.

S. No.	Column I	S. No.	Column II
A.	Cleavage	1.	Outer layer of the blastocyst that attaches to the endometrium during implantation.
B.	Implantation	2.	Mitotic divisions of the zygote in quick succession.
C.	Inner cell mass	3.	Embedding of the blastocyst in the endometrium of uterus.
D.	Trophoblast	4.	Release of secondary oocyte from the ovary.
E.		5.	Group of cells attached to one end of trophoblast that differentiate into embryo proper.

If you squeeze a seed of orange you might observe many embryos of different sizes? How is it possible? Explain.

Is haemophilia in humans a sex-linked or autosomal disorder? Work out a cross in support of your answer.

What is a carcinogen? Name one chemical carcinogen with its target tissue?

(a) Name the organic material exine of the pollen grain is made-up of. How is this material advantageous to pollen grain?
(b) Still it is observed that it does not form a continuous layer around the pollen grain. Give reason.
(c) How are 'Pollen banks' useful ?

In the pie chart (a) and (b) drawn below to show the global animal diversity, which group of animals would you name and write on the areas shaded back in (a) and (b). In which kind of habitat would you find these groups of animals?

What is meant by gene cloning?