Long Answer TypeGive reasons why:
a. Most zygotes in angiosperms divide only after certain amount of endosperm is formed.
b. Groundnut seeds are exalbuminous and castor seeds are albuminous.
c. Micropyle remains as a small pore in the seed coat of a seed.
d. Integuments of an ovule harden and the water content is highly reduced, as the seed matures.
e. Apple and cashew are not called true fruits.
Describe the mechanism of pattern of inheritance of ABO blood groups in humans.
In humans, the ABO blood groups are controlled by a gene called I gene. It has three alleles, namely IA, IB and i. A person possesses any two of the three alleles. IA and IB dominate over i. But with each other, IA and IB are co-dominant that is they both get expressed when present together.
IA and IB are responsible for the production of antigen A and B present on the surface of RBC. Plasma membrane of RBC possess sugar polymer that protrudes out of its surface and the type of sugar present on the surface is controlled by gene I. IA and IB allele is responsible for coding for glycosyltransferase enzyme responsible for developing modification in the terminal sugar molecule. IA and IB differ very minutely on the sugar molecule while gene i does not produce any sugar molecule. Here allele A and B are dominant in nature while ii fail to produce any antigenic molecule so express blood group O. 
A. Why is haemophilia generally observed in human males? Explain the conditions under which a human female can be haemophilic.
B. A pregnant human female was advised to undergo M.T.P. It was diagnosed by her doctor that the foetus she is carrying has developed from a zygote formed by an XX egg fertilized by Y-carrying sperm. Why was she advised to undergo M.T.P.?
A. Describe the characteristics a cloning vector must possess.
B. Why DNA cannot pass through the cell membrane? Explain. How is a bacterial cell made competent to take up recombinant DNA from the medium?
If a desired gene is identified in an organism for some experiments, explain the process of the following:
(i) Cutting this desired gene at specific location
(ii) Synthesis of multiple copies of this desired gene
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