The allele for curly hair is incompletely dominant. If a mother is homozygous for curly hair and the father is homozygous for straight hair, what percentage of the offspring will exhibit characteristics of both parents?

1 Answer
Jun 20, 2018




Let's start with a definition of incomplete dominance. Incomplete dominance is when a heterozygous individual displays a mix of phenotypes for a trait. For instance, red flowers being a dominant allele and white flowers being a recessive allele in roses; if a heterozygous individual is a mix of the colors (pink), we have incomplete dominance.

Now the genetics part:

Let's assume curly hair is the dominant trait and trait hair is the recessive trait.

Therefore, our cross is AA x aa. Drawing a punnett square will then give us all heterozygous individuals.

Going back to our definition of incomplete dominance, we can say that 100% of the offspring will exhibit characteristics of both parents.