Which of the following is an example of incomplete dominance in inheritance?

• A. Black and white speckled feathers in chickens
• B. AB blood type in humans
• C. Green and yellow peas in Mendel's experiments
• D. Pink flowers in snapdragons resulting from red and white parent flowers

Answer: (D)

Verified step by step guidance

1. Understand the concept of incomplete dominance: Incomplete dominance is a form of inheritance where the phenotype of a heterozygote is intermediate between the phenotypes of the two homozygotes. This means that neither allele is completely dominant over the other.
2. Identify the examples given: The problem provides several examples of inheritance patterns, including black and white speckled feathers in chickens, AB blood type in humans, green and yellow peas in Mendel's experiments, and pink flowers in snapdragons.
3. Analyze each example: Determine which example fits the definition of incomplete dominance. In incomplete dominance, the offspring's phenotype is a blend of the parents' phenotypes.
4. Focus on the example of pink flowers in snapdragons: In snapdragons, when a red-flowered plant is crossed with a white-flowered plant, the offspring have pink flowers. This is a classic example of incomplete dominance, where the red and white alleles blend to produce an intermediate phenotype.
5. Conclude that pink flowers in snapdragons are the correct example of incomplete dominance: The pink flowers result from the blending of red and white alleles, demonstrating the intermediate phenotype characteristic of incomplete dominance.