Males are more often affected by sex-linked traits than females because
A)sex-linked traits are located on autosomes that affect males more severely than females.
B)the presence of a Y chromosome often worsens the effects of X-linked mutations.
C)X chromosomes in males generally have more mutations than X chromosomes in females.
D)males are hemizygous for the X chromosome.

Question

Quizplus · Accepted Answer

Males have only one X chromosome, making them hemizygous for sex-linked traits. If they inherit a recessive allele for a sex-linked trait, they will express it because they don't have a second X chromosome with a dominant allele to mask the recessive trait. Females typically have two X chromosomes, so they have a higher chance of having at least one dominant allele that could mask a recessive trait on the other chromosome.

Males Are More Often Affected by Sex-Linked Traits Than Females