In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced.
-Give genotypes for comb shape of the parents in the following cross: Rose crossed with walnut produces 6 walnut, 6 rose, 2 single, and 2 pea offspring.
A) RR pp × rr PP
B) Rr pp × rr Pp
C) Rr pp × rr PP
D) RR pp × rr Pp
E) Rr pp × Rr Pp

Question

In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. 
-Give genotypes for comb shape of the parents in the following cross: Rose crossed with walnut produces 6 walnut, 6 rose, 2 single, and 2 pea offspring.
A) RR pp × rr PP
B) Rr pp × rr Pp
C) Rr pp × rr PP
D) RR pp × rr Pp
E) Rr pp × Rr Pp

Quizplus · Accepted Answer

The Answer of In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant gene R is present at one locus and at least one dominant gene P is present at a second locus (genotype R_ P_). A rose comb is produced when at least one dominant gene is present at the first locus and two recessive genes are present at the second locus (genotype R_ pp). A pea comb is produced when two recessive genes are present at the first locus and at least one dominant gene is present at the second (genotype rr P_). If two recessive genes are present at the first and the second locus (rr pp), a single comb is produced. 
-Give genotypes for comb shape of the parents in the following cross: Rose crossed with walnut produces 6 walnut, 6 rose, 2 single, and 2 pea offspring.
A) RR pp × rr PP
B) Rr pp × rr Pp
C) Rr pp × rr PP
D) RR pp × rr Pp
E) Rr pp × Rr Pp

In Chickens, Comb Shape Is Determined by Genes at Two