Suppose that tomatoes with the RR genotype are red and those with rr are green.Assuming that this reflects conventional genetics shorthand of upper- and lowercase letters, which situation is true?
A) R is dominant to r, and Rr individuals are green.
B) R is dominant to r, and Rr individuals are red.
C) r is dominant to R, and Rr individuals are green.
D) r is dominant to R, and Rr individuals are red.
E) r is dominant to R, and Rr individuals are yellow.

Question

Quizplus · Accepted Answer

In conventional genetics shorthand, uppercase letters represent dominant alleles and lowercase letters represent recessive alleles. Therefore, R must be dominant to r. The homozygous dominant genotype would be RR and the homozygous recessive genotype would be rr. The heterozygous genotype would be Rr. Because R is dominant, individuals with at least one R allele (i.e. RR or Rr) will have the red phenotype. Thus, option B is correct as it explains that R is dominant to r and individuals with the heterozygous Rr genotype will be red.

Suppose That Tomatoes with the RR Genotype Are Red and Those