3) (8 pts) In a species of tree, seed color is determined by four independently assorting genes: A, B, C, and D. The recessive alleles of each of these genes (a, b, c, and d) produce abnormal enzymes that cannot catalyze a reaction in the biosynthetic pathway for seed pigment. This pathway is diagrammed as follows: White precursor - Yellow - Orange - Red - Blue. When both red and blue pigments are present, the seeds are purple. Trees with the genotypes of Aa Bb Cc Dd and Aa Bb Cc dd were crossed. (a) (2 pts) What color are the seeds in these two parental genotypes? (b) (2 pts) What proportion of the offspring from the cross will have white seeds? (c) (4 pts) Determine the relative proportions of red, purple, blue, and orange offspring from the cross.

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