Imagine a diploid cell with the genotype AaBb, and assume that the A and B genes assort independently. If this cell undergoes meiosis, how many different genotypes could the resulting haploid cells have?

Mendel's law of independent assortment of genes states that the alleles of two or more different genes get sorted into gametes independent of one another i.e. the allele a gamete receives for one gene does not affect the allele received for another gene.

In this case, a F1 generation has resulted from the cross between a homozygous dominant parent (AABB) and a homozygous recessive parent (aabb). This F1 generation (AaBb) is said to be a dihybrid because it contains an heterozygous allele for two different genes.

The dihybrid undergoes meiosis and results into four genotypically different types of haploid gametes (sperm and eggs) with equal frequency i.e. if each gamete randomly got an A or a allele and in a separate process, also randomly got a B or b allele.

The four possible combinations of haploid gametes are: AB, Ab, aB, and ab