Question

In humans the allele for curly hair and the allele for straight hair show incomplete dominance. If two people with wavy hair have offspring, what percentage of their offspring would you expect to have wavy hair?

A.) 100% B.) 75% C.) 50% D.) 25% Would it be 50%?!

Answer 1

It would be 50% if the allele for wavy hair was Ww.

Answer 2

C.) 50%

Step-by-step explanation:

Suppose W is the allele for straight hair and w is the allele for curly hair. The two traits show incomplete dominance which means that homozygous WW will result in straight hair, homozygous ww will result in curly hair and heterozygous Ww will show the blend of two traits i.e. wavy hair.

Now, parent 1 : wavy hair = Ww

parent 2 : wavy hair = Ww

Their offspring = Ww X Ww :

W w

W WW Ww

w Ww ww

As evident, 50% of the offspring has Ww genotype hence 50% of the offspring will have wavy hair.