Question

Red-green color blindness is due to an X-linked recessive allele in humans. A widow’s peak (a hairline that comes to a peak in the middle of the forehead) is dueto an autosomal dominant allele.
Consider the following family history:

A man with a widow’s peak and normal color vision marries a color-blind woman with a straight hairline.
The man’s father had a straight hairline, as did both of the woman’s parents.

Use the family history to make predictions about the couple’s children.
Drag the correct label to the appropriate location in the table. Not all labels will be used.

Answer 1

1) 1/2 this is due to the fact that the father is hetereozygous Ww (my version of widows peak :) )

2) 1/2 * 1 = 1/2 ; the 1 comes from the probability of the son being colorblind

3) 1/2 * 0 = 0 is answer ; 0 comes from the fact that there is 0 probability of the daughter being colorblind since she gets her willdtype phenotype fromdad

4) 1/2 * 1/2 = 1/4 ; For this one you have to place into account for two events occuring; The daughter must be heterzygous normal (1/2) AND must beheterzygous for Widows peak (1/2)

Hopefully this helps....

Answer 2

1. 1/4 2. 1/2 3. 0 4. 1