Question

Differentiate between co-dominance and incomplete dominance.

Hint:

In co-dominance, both traits are fully visible, while in incomplete dominance, the traits mix.

Answer 1

Step 1: Definition of Co-Dominance
Co-dominance occurs when both alleles contribute equally and visibly to the organism's phenotype. For example, in the case of blood type, the alleles A and B are co-dominant, both being expressed in the heterozygote.
Step 2: Definition of Incomplete Dominance
Incomplete dominance occurs when neither allele is fully dominant over the other, leading to a blending of traits in the offspring. For example, when a red flower (RR) is crossed with a white flower (WW), the offspring may be pink (RW), a mixture of the two.
Step 3: Key Differences
- Co-dominance: Both alleles are expressed equally in the phenotype (e.g., AB blood type). - Incomplete Dominance: The phenotype is a blend of the two alleles (e.g., pink flowers from red and white parents).
Final Answer: In co-dominance, both alleles are expressed equally, while in incomplete dominance, the alleles blend to form an intermediate phenotype.