In poultry,the genes for rose comb (R)and pea comb (P)produce walnut whenever they occur together (R__ P__); single-combed individuals have the homozygous condition for both genes (rr pp).Give the phenotypic results of a cross of Rr Pp x rr Pp
A) 9/16 walnut, 3/16 rose, 3-16 pea, 1/16 single
B) 3/8 walnut, 3/8 pea, 1/8 rose, 1/8 single
C) 3/4 walnut, 1/4 rose
D) 1/4 walnut, 1/4 rose, 1/4 pea, 1/4 single.
E) 1/4 walnut, 1/4 rose, 1/4 pea, 1/4 single..

Question

In poultry,the genes for rose comb (R)and pea comb (P)produce walnut whenever they occur together (R__ P__); single-combed individuals have the homozygous condition for both genes (rr pp).Give the phenotypic results of a cross of Rr Pp x rr Pp  
A) 9/16 walnut, 3/16 rose, 3-16 pea, 1/16 single
B) 3/8 walnut, 3/8 pea, 1/8 rose, 1/8 single
C) 3/4 walnut, 1/4 rose
D) 1/4 walnut, 1/4 rose, 1/4 pea, 1/4 single.
E) 1/4 walnut, 1/4 rose, 1/4 pea, 1/4 single..

Quizplus · Accepted Answer

The Punnett square for the cross is:

| R | r |
---|---|---|
P |RP | rP |
p |Rp | rp |

From this square, we can see that:

- 3/8 of the offspring will have walnut comb (RP or Rp)
- 3/8 of the offspring will have pea comb (rP or rp)
- 1/8 of the offspring will have rose comb (rP)
- 1/8 of the offspring will have single comb (rp)

In Poultry,the Genes for Rose Comb (R)and Pea Comb (P)produce