Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Write three example of mendelian disorders and explain any one of them.

What is the function of bulbourethral glands?

Write the differences between male and female gametophyte.

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.

What will be the ploidy of the cells of the nucellus, microspore mother cell, the functional megaspore and female gametophyte?

Palaeontological evidence support the theory of organic evolution. Explain with an example.

Name and explain three adaptations of mangroves to the conditions prevailing in Sunderbans (West Bengal).

Draw a transverse sectional view of an apple and label the following parts along with their technical names:

1. Edible part.
2. Encloses the embryo.
3. Forms the fruit wall.

Haemophilia is a sex-linked recessive disorder of humans. The pedigree chart given below shows the inheritance of haemophilia in one family. Study the pattern of inheritance and answer the questions given.

1. Give all the possible genotypes of the members 4; 5 and 6 in the pedigree chart.
2. A blood test shows that the individual 14 is a carrier of haemophilia. The member numbered 15 has recently married the member numbered 14. What is the probability that their first child will be a haemophilia male?