The Red Kernel Color in Wheat Is Caused by the Presence

Multiple Choice

The red kernel color in wheat is caused by the presence of at least one dominant allele in each of two independently segregating gene pairs (e.g., R_B_) . Wheat plants with rrbb genotypes have white kernels, and plants with genotypes R_bb and rrB_ have yellow kernels. You cross a plant homozygous for red kernels (RR BB) with a plant homozygous for white kernels. What are the relative proportions of the phenotypic classes expected in the F₂ progeny after selfing the F₁ progeny?

A) 9 red; 3 white; 4 yellow
B) 9 red; 6 yellow; 1 white
C) 9 yellow; 4 red; 1 white
D) 9 red; 3 yellow; 4 white
E) 12 red; 3 yellow; 1 white