Question

In humans, colorblindness is sex linked and recessive. If a woman is a carrier for the trait, what is the chance that her sons will be colorblind? Her daughters? (Assume their father has normal vision.)

Answer 1

Answer:

50% for sons 0%for daughters

Explanation:

the genotype of the mother is X⁻X

the genotype of the father is XY

the gametes from the mother are X⁻ andX

the gametes from the father are X and Y

to find the chance we make a Punnet square and cross each gamete

$\left[\begin{array}{ccc}X^-X&XX\\X^-Y&XY\end{array}\right]$

1 of the 2 males has the gene for colorblindness so there is a 50% chance that the son will be colorblind

1 of the 2 daughters has the gene for cloroblindness but only in one exemplary so the chance is 0%