AP BIOLOGY

Detailed explanation-1: -Half shaded circle and square are used for heterozygous for autosomal recessive. Full shaded circle and square are used for affected individuals. A square with a diagonal line is used for death.

Detailed explanation-2: -A half-shaded circle or square indicates that a person is a carrier of the trait. A completely shaded circle or square indicates that a person expresses the trait. A circle or square that is not shaded indicates that a person neither expresses the trait nor is a carrier of the trait.

Detailed explanation-3: -TT represents a homozygous dominant genotype. tt represents a homozygous recessive genotype. Tt represents a heterozygous genotype.

Detailed explanation-4: -In pedigrees, heterozygous individuals are represented by half-shaded symbols (just like carriers in pedigrees for sex-linked traits).

Detailed explanation-5: -Homozygous. Having two identical alleles for a particular gene. Heterozygous. Having two different alleles for a particular gene.