Snapdragons are flowers that come in a variety of colors,including red,pink,and white.A series of crosses with snapdragons having flowers of different colors produced the following results: pink × pink: 27 pink,13 red,14 white
Red × red: all red
White × white: all white
Pink × white: 29 pink,26 white
Pink × red: 28 pink,27 red
White × red: all pink
Based on the results,what is the most reasonable explanation for the inheritance of these flower colors?

Question

Quizplus · Accepted Answer

The results of the crosses suggest that the inheritance of flower color in snapdragons is exhibiting incomplete dominance, where the heterozygous individuals (pink x pink and pink x white) produce an intermediate phenotype between the two homozygous parents. This is evident in the ratios produced by the pink x pink cross and the pink x white cross, where both crosses produced a mixture of pink and white flowers. The red x red cross produced all red flowers, indicating that this trait is determined by a single gene, but the lack of any intermediate colors suggests that the inheritance pattern is not codominant or pleiotropic. The white x white cross also produced all white flowers, indicating that the allele for white flowers is homozygous recessive. The pink x red cross produced a mixture of pink and red flowers, but not in the 1:1 ratio that would be expected for codominance, again suggesting incomplete dominance as the most likely explanation. There is no evidence to suggest that there are more than two alleles at play, and qualitative effects would result in distinct color categories rather than intermediate colors.

Snapdragons Are Flowers That Come in a Variety of Colors,including