question_answer

In cats, the genes controlling coat-colour are codominant (incompletely dominant) and are carried on the X-chromosomes. When a black female was mated with a ginger male, the resulting litter consisted of black male and tortoise shell female kittens. What phenotypic ratio would be expected in the \[{{F}_{2}}\text{-}\]generation?

A) 1 black male: 1 ginger male; 2 tortoise shell females

B) 1 black male: 1 ginger male; 1 tortoise shell female: 1 black female

C) 2 black males: 1 tortoise shell female: 1 ginger female

D) 1 black male: 1 tortoise shell male: 1 ginger female: 1 black female

Correct Answer: B

Solution :

B: allele for black coat G: allele for ginger coat