If the parent genotypes are AA and aa, what is the expected genotype of the offspring?

The expected genotype of the offspring in this scenario can be determined through a basic understanding of Mendelian genetics. When one parent has the genotype AA, it means they are homozygous for the dominant allele A. The other parent, with the genotype aa, is homozygous for the recessive allele a.

When these two parents interbreed, all offspring will inherit one allele from each parent. The AA parent can only contribute the dominant allele A, and the aa parent can only contribute the recessive allele a. Therefore, every offspring will receive one A from the AA parent and one a from the aa parent, resulting in the genotype Aa for all offspring.

This situation illustrates the principles of dominance and segregation as proposed by Gregor Mendel. Since the only combination possible from these two parent genotypes is Aa, the offspring will all display this genotype, demonstrating a classic example of how alleles combine in offspring.