Question In a certain pepper plants the color of the peppers

Question:

In a certain pepper plants, the color of the peppers from an individual plant can be either all yellow or all red. The R allele produces red peppers while the recessive allele generates yellow peppers. If a pepper plant that is heterozygous for these alleles is mated with a genetically similar plant, what percentage of the red-pepper progeny will be heterozygous for the alleles that control pepper color?

A) 25%

B) 33%

C) 50%

D) 67%

E) 75%

Solution

Answer is option C. 50%

R=red r=yellow. R is dominant. If Rr is crossed with Rr, then the genotypes of the progeny would be RR, Rr, Rr and rr.

75% of the progeny would be red (RR, Rr and Rr). Of these 50% are heterozygous (Rr and Rr).