How does incomplete dominance differ from co-dominance in inheritance patterns?

Incomplete dominance results in a blended phenotype, while co-dominance results in both traits being expressed simultaneously.

Incomplete dominance and co-dominance are two types of non-Mendelian inheritance patterns that occur when two different alleles for a trait are present in a genotype. In incomplete dominance, neither allele is completely dominant over the other. Instead, the phenotype of the heterozygous individual is a blend of the phenotypes of the homozygous individuals. For example, if a flower species has a red allele (R) and a white allele (W), and neither is dominant, a plant with the genotype RW would have pink flowers. This is because the red and white traits blend together to create a new phenotype.

On the other hand, co-dominance is a situation in which both alleles are equally dominant and both traits are expressed simultaneously in the phenotype. This means that the heterozygous individual will display both traits at the same time, rather than a blend of the two. A classic example of co-dominance is the AB blood type in humans. Individuals with this blood type have both A and B antigens on the surface of their red blood cells because they inherited an A allele from one parent and a B allele from the other. Neither allele is dominant or recessive, so both are expressed.

In summary, the key difference between incomplete dominance and co-dominance lies in the phenotype of the heterozygous individual. In incomplete dominance, the phenotype is a blend of the two homozygous phenotypes, while in co-dominance, both traits are expressed simultaneously. Understanding these patterns of inheritance can help us predict the possible outcomes of genetic crosses and better understand the complex nature of heredity.