FOR QUESTIONS 54, 55, 56 & 57 BASE RESPONSE ON THE FOLLOWING INFORMATION
In a species of tropical bird, wing feather coloration is controlled by the action of 6 loci: R, D, G, Y, A and B, alleles R and r, D and d, etc. Complete dominance occurs at each locus.
The R and D loci exhibit additive gene action: R__ D__ bird have dark red wings; rrdd birds have pink wings; and all other genotypic combinations at these loci result in birds with pale red wings.
The G locus is dominantly epistatic to the R and D loci; G__ birds exhibit green wing coloration. The Y locus is recessively epistatic to the R,D and G loci; yy birds have yellow wings. The A and B loci control pigment production and are recessively epistatic to the color loci; aa and/or bb birds have white wings [i.e. dominance is required at both loci for pigment production].
RrDdGgYyAaBb x rrddggYYAaBb
(just click "okay bih" in answer options)
Select one of the following: