Final answer:
The likely genotype of the offspring (person 3) when both parents (person 1 and person 2) are heterozygous (Aa) is indeterminable without additional phenotype or inheritance pattern information, though there are possibilities for the offspring to be homozygous dominant (AA), heterozygous (Aa), or homozygous recessive (aa).
Step-by-step explanation:
If both person 1 and person 2 are heterozygous, represented by the genotype Aa, and they were to have offspring, denoted as person 3, we can predict the likely genotype of person 3 using a simple Punnett square to determine all possible genotypes for their offspring. According to Mendelian genetics, there is a 1 in 4 chance that the offspring will be homozygous dominant (AA), a 1 in 2 chance that the offspring will be heterozygous (Aa), and a 1 in 4 chance that the offspring will be homozygous recessive (aa). Therefore, the likely genotype of their offspring could either be homozygous dominant, heterozygous, or homozygous recessive but without additional information such as the phenotype of person 3 or the pattern of inheritance, we cannot determine the exact genotype of person 3.
Given that both parents have at least one normal allele as they are heterozygous, it's crucial to understand that while their offspring have possibilities of different genotypes, the actual genotype for each child is a result of random assortment and segregation of alleles during gamete formation and fertilization.