What phenotype results from two heterozygous alleles in incomplete dominance?

What phenotype results from two heterozygous alleles in incomplete dominance?

• A. A fully dominant phenotype
• B. No expression
• C. A single allele
• D. A blended phenotype

Answer: (D)

Incomplete dominance occurs when neither allele is fully dominant, so the heterozygous genotype expresses a phenotype that sits between the two homozygous phenotypes. With two different alleles, you don’t get a fully dominant form or no expression; you get a blended appearance. A classic example is snapdragon flower color, where red and white parents produce pink offspring in the heterozygous state. This blending aligns with the idea that both alleles contribute to the trait, producing an intermediate phenotype.

Incomplete dominance occurs when neither allele is fully dominant, so the heterozygous genotype expresses a phenotype that sits between the two homozygous phenotypes. With two different alleles, you don’t get a fully dominant form or no expression; you get a blended appearance. A classic example is snapdragon flower color, where red and white parents produce pink offspring in the heterozygous state. This blending aligns with the idea that both alleles contribute to the trait, producing an intermediate phenotype.