Each question has only ONE correct answer. A brown rabbit is crossed with a white rabbit and the F1 offspring are 4 brown and 3 white. O confers orange and X B confers black. A plant with yellow chloroplasts is pollinated with pollen from a plant with green chloroplasts, and all the resulting progeny have yellow chloroplasts. In sweet peas, flower color is controlled at one locus with pink being dominant to white.
Scent is controlled at another unlinked locus with scented being dominant to non-scented.
Individuals suffering from the genetic disease phenylketonurea have abnormally small heads and light-colored hair in addition to being unable to metabolize phenylalanine. Twin sisters, separated at birth, meet after 30 years and they find that one has two children and the other has three. A man with a hereditary skin condition marries a phenotypically normal woman. Write your answer in the spaces provided. Hemophilia in humans is caused by a recessive X-linked allele.