Explain incomplete dominance, using snapdragon flowers as an example.

1 answer

Incomplete dominance is a genetic phenomenon where neither of the alleles for a particular trait is completely dominant over the other, resulting in a phenotype that is a blend of the two alleles.

Snapdragon flowers provide a classic example of incomplete dominance. In snapdragons, the gene for flower color has two alleles: red (R) and white (r). When a plant carries two red alleles (RR), the flowers are red. When a plant carries two white alleles (rr), the flowers are white. However, when a plant carries one red and one white allele (Rr), the flowers are pink, displaying a blend of red and white.

This phenomenon illustrates how incomplete dominance results in an intermediate phenotype, where both alleles contribute to the final expression of the trait.