Freckles dominate in humans. In the family, both parents have freckles

Freckles dominate in humans. In the family, both parents have freckles, but their daughter does not. How many gamete types does a man have?

Let us designate the gene that causes the development of freckles in humans as B, and the gene that, in a homozygous state, leads to their absence, as in.

The daughter does not have freckles, therefore, she is, because homozygosity for the phenotypic realization of this trait is a necessary condition.

Such a genotype is formed by the fusion of an egg cell and a sperm cell. Consequently, both parents must carry the gene for the recessive trait in their genotypes. Since both parents have freckles – they are heterozygous – BB. Such parents produce two types of germ cells – b and B.

Answer: There are 2 types of gametes.