In chickens, congenital baldness results from a Z-linked recessive gene. A bald rooster is mated with a normal hen. The Fi from this corss are interbred to produce the F2 ... The F2 progeny will include?

A. only normal roosters & hens

B. only bald roosters & hens

C. only normal roosters & bald hens

D. only bald roosters & normal hens

E. normal roosters & hens and bald roosters & hens

E. normal roosters & hens and bald roosters & hens.

Explanation:

The sex chromosomes of the chickens are represented by ZZ for male chicken that is rooster and ZW for the female chicken that is hen.

In the given question, the genotype of the bald rooster is zz and the genotype of the normal hen is ZW.

So the F1 progeny are, Zz that is normal male and the zW that is bald female.

So F1 * F1

Zz * zW

Thus, F2 progeny are Zz (normal rooster), zz (bald rooster), ZW (normal hen), zW (bald hen).