A couple has three children,two of which have blonde hair.The third child and both parents have dark hair.What can be determined about the gene for hair color in this family?
A) It is an autosomal recessive trait.
B) It is an autosomal dominant trait.
C) It is a sex-linked dominant trait.
D) It is a sex-linked recessive trait.
E) It conveys a lethal mutation.

Question

Quizplus · Accepted Answer

Since both parents have dark hair and two of their children have blonde hair, the trait for blonde hair must be recessive. Therefore, the gene for hair color in this family is an autosomal recessive trait.

A Couple Has Three Children,two of Which Have Blonde Hair