In Drosophila,the recessive allele for forked bristles is sex-linked,and the recessive allele for purple eyes is autosomal.The wild-type alleles are for straight bristles and red eyes,respectively.A female,heterozygous for both pairs of alleles,is mated with a male with forked bristles and purple eyes.What percentage of the daughters will have forked bristles and purple eyes?
A) 100%
B) 75%
C) 50%
D) 25%
E) 0%

Question

Quizplus · Accepted Answer

Since the gene for forked bristles is sex-linked and the female is heterozygous, she will pass on the allele for forked bristles to half of her daughters. The gene for purple eyes is autosomal recessive, and since the female is heterozygous and the male has purple eyes, half of their offspring will inherit the purple eyes phenotype. Therefore, 1/2 (for forked bristles) * 1/2 (for purple eyes) = 1/4 or 25% of the daughters will have both forked bristles and purple eyes.

In Drosophila,the Recessive Allele for Forked Bristles Is Sex-Linked,and the Recessive