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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.)

User Keeleon
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1 Answer

6 votes

Answer:

50% for sons 0%for daughters

Step-by-step 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%

User Mario Lopez
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