Hemophilia is a bleeding disorder that primarily affects males. Which of the following statements best explains why females are less likely to express the trait.(1 point)

Question

Responses

When paired with a normal X, the affected x allele is masked (Xx), suppressing the trait. Since females have only X alleles, the probability increases.
When paired with a normal X, the affected x allele is masked (Xx), suppressing the trait. Since females have only X alleles, the probability increases.

Females have an XY chromosome pair, so the trait is frequently expressed
Females have an XY chromosome pair, so the trait is frequently expressed

Males without an affected x allele always express the trait (XY)
Males without an affected x allele always express the trait (XY)

When paired with a normal X, the affected x allele is masked (Xx), suppressing the trait. Since females have only X alleles, the probability decreases.

Answer 1

The statement that best explains why females are less likely to express hemophilia is:

"When paired with a normal X, the affected x allele is masked (Xx), suppressing the trait. Since females have only X alleles, the probability decreases."

This is because females have two X chromosomes (XX), so if one X chromosome carries the hemophilia allele, the other normal X can mask the effects of the affected allele. In contrast, males have one X and one Y chromosome (XY), so they will express hemophilia if their single X chromosome carries the affected allele.