Explain why the statement below is true:a person with curly hair may be heterozygous or homozygous

Answer 1

To my understanding, hair type (such as straight or curly) is a trait that exhibits incomplete dominance. This means that if someone were heterozygous for hair type, they would have "wavy" hair or something in between curly and straight. So if you count wavy hair like curly, then you could have an individual who's either homozygous for the curly hair allele or heterozygous with both curly and straight alleles.

Now, I'm not sure whether your professor is expecting a clear answer to this question, but in any case, I would probably go with the incomplete dominance explanation and assume curly includes "wavy". However, I have found online that some people say that curly hair is actually a dominant allele, and that hair type follows classical Mendelian inheritance rules. If that's the case, then the answer to this would be much simple and would be that someone who is homozygous for the curly allele, as well as someone who is heterozygous, would both present curly hair given that it is the dominant allele.

Hope this helps!