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 due to 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.

let small x be color blindness and capital P be widows peak now man has widows peak. his father was normal. so obviously mother has widows peak. so the man is heterozygous. so genotype of man is PpXY capital X becaude he has normal vision. Women's genotype is ppxx according to the given phenotype. PpXY X ppxx gametes - PX PY pX pY px so possible genotype of children - PpXx (widow peak, normal girl) PpxY (widow peak, color blind boy) ppxx (normal, colorblind girl) ppxY (normal, colorblind boy))