7. In sweet peas, the synthesis of purple anthocyanin pigment in
the petals is controlled by two genes, B and D. The pathway is:

White intermediate —Gene B –> Blue intermediate —Gene D
–> Anthocyanin (purple)

a. What color petals would you expect in a pure-breeding plant
unable to catalyze the first reaction?

b. What color petals would you expect in a pure-breeding plant
unable to catalyze the second reaction?

c. If the plants in parts a and b are crossed, what color petals
will the F1 plants have? d. What ratio of purple:blue:white plants
would you expect in the F2?

d. What ratio of purple:blue:white plants whould you expect in
the F2?