Two mice breed. The male is heterozygous for the dominant traits of black fur and active behavior but is homozygous recessive for light eyes. The female mouse is heterozygous for dark eyes, has white fur, and displays lazy behavior. How many types of gametes does the male mouse produce?

Four

Explanation:

Let the allele for black fur be B (the alternate will be b), the allele for active behavior be A (the alternate will be a), and the allele for light eyes be L (the alternate will be l).

Heterozygous dominant for black fur = Bb

Heterozygous dominant for active behavior = Aa

Homozygous recessive for light eyes = ll

Hence, the genotype for a male that is heterozygous for the dominant traits of black fur and active behavior but is homozygous recessive for light eyes will be BbAall.

Bb   Aa   ll

Possible Gametes

BAl, Bal, bAl, and bal

Therefore, the number of different types of gametes produced by the male mouse is four.