In cats, black fur color is caused by an X-linked allele; the other allele at this locus causes orange color. The heterozygote is tortoiseshell. What kinds of offspring would you expect from the cross of a black female and an orange male?
A)Tortoiseshell females; tortoiseshell males
B)Black females; orange males
C)Orange females; orange males
D)Tortoiseshell females; black males
E)Orange females; black males

Question

Quizplus · Accepted Answer

Since the black fur color is X-linked, the female offspring will inherit one X chromosome from each parent. The black female will have one X with the black allele and one X with the orange allele. The orange male will have one X with the orange allele and one Y chromosome. Therefore, all female offspring will be heterozygous for black and orange alleles and will be tortoiseshell. The male offspring will inherit either an X with the black allele and a Y from the father, making them black, or an X with the orange allele and a Y from the father, making them orange. Therefore, there will be black male offspring and orange male offspring.

In Cats, Black Fur Color Is Caused by an X-Linked