In a cross with a mother who carries the allele for hemophilia and a father who has normal blood clotting what would be the expected phenotypes of the offspring?

Question

A. all females normal, all males normal
B. all females normal, all males with hemophilia
C. all females carriers of hemophilia, all males normal
D. one female normal, one male normal, one female carrier, one male with hemophilia

here's my work:

XCXC, XcY

XCXc, XCXc, XCY, XCY

doesnt this mean that all the girls have hemophilia, and all the boys are normal?

Answer 1

The girls all receive normal X chromosome from dad, meaning they cannot be more than carriers. If males get recessive gene, they will have hemophilia since there is no dominant gene on the Y chromosome to supress the hemophilia gene.

How do you get six variations?

XCXC, XcY

XCXc, XCY