In a dihybrid cross, how many different gametes can be produced by an organism that is heterozygous for both genes?

In a dihybrid cross, when an organism is heterozygous for two genes, it means that it has two different alleles for each gene. The formula to determine the number of different gametes produced is based on the number of heterozygous gene pairs. Each gene can independently assort during gamete formation, leading to various combinations of alleles.

For two genes, each heterozygous (let’s use A/a and B/b for reference), the combinations of alleles that can be formed are:

• From the first gene (A/a), the gametes can contain either A or a.

• From the second gene (B/b), the gametes can contain either B or b.

To calculate the total number of different gametes, you multiply the number of combinations from each gene. In this scenario:

• For the first gene, there are 2 possible alleles (A or a).

• For the second gene, there are also 2 possible alleles (B or b).

Thus, the total number of gametes produced is 2 (from the first gene) multiplied by 2 (from the second gene), which equals 4. Since this is a dihybrid cross, the combination of