Question

incomplete dominance governs the pigment gene of a flower. a mating between heterozygotes yields the following phenotypic ratio: 15 red flowers, 32 pink flowers and 14 white flowers. which statement describes the situation? the heterozygotes were red. the flower pigment gene is defined by a red and a white allele. the heterozygotes were white. the flower pigment gene is defined by a pink and red allele.

Explanation:

• In incomplete dominance, the heterozygote shows an intermediate phenotype. Here, pink is the intermediate between red and white.
• Let's assume the alleles: if \(R\) (red) and \(r\) (white) are the alleles. The homozygous \(RR\) would be red, \(rr\) white and \(Rr\) (heterozygote) pink.
• The phenotypic ratio \(15:32:14\) (approx \(1:2:1\)) is consistent with a cross \(Rr\times Rr\) (\(RR:Rr:rr = 1:2:1\) in a Mendelian sense for incomplete - dominance).

Answer:

The flower pigment gene is defined by a red and a white allele.