Question

The person A has only B chromosomes in all its gametes. On the other hand, another person C has chromosome D in half of gametes and chromosome E in the other half of gametes. When chromosomes B and D combine during fertilisation, a female zygote results. On the other hand, combination of B and E chromosomes produces a male zygote.
(a) What are chromosomes (i) B (ii) D, and (iii) E?
(b) Out of B, D and E, which two chromosomes are of the same type?
(c) Which chromosome is smaller in size?
(d) What is the general name of chromosomes such as B and E?
(e) Out of the two persons A and C, which one is (i) male, and (ii) female?

Answer 1

(a) (i) B is X chromosome; (ii) D is also X chromosome; (iii) E is Y  chromosome.
(b) Chromosomes B and D are of same type.
(c) Chromosome E is smaller in size.
(d) Chromosomes B and E are called sex chromosomes.
(e) (i) A is female; (ii) C is male.