AP BIOLOGY

Detailed explanation-1: -Number of genotypes for a given number of alleles Given n alleles at a locus, the number genotypes possible is the sum of the integers between 1 and n: With 2 alleles, the number of genotypes is 1 + 2 = 3.

Detailed explanation-2: -Genotype is also used to refer to the pair of alleles present at a single locus. With alleles ‘A’ and ‘a’ there are three possible genotypes AA, Aa and aa. With three alleles 1, 2, 3 there are six possible genotypes: 11, 12, 13, 22, 23, 33.

Detailed explanation-3: -Since there are three different alleles, six different genotypes are possible.

Detailed explanation-4: -Each pair of alleles represents the genotype of a specific gene. Genotypes are described as homozygous if there are two identical alleles at a particular locus and as heterozygous if the two alleles differ. Alleles contribute to the organism’s phenotype, which is the outward appearance of the organism.