NEET BIOLOGY

Detailed explanation-1: -In human pedigree analysis, full shaded symbols represent the affected individuals while the half shaded stands for carriers. Square shape stands for male individual while the circle stands for females. The unidentified sex is represented by diamond shape.

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: -A male is represented by a square or the symbol ♂, a female by a circle or the symbol ♀. Mating is shown by a horizontal line (marriage line) connecting a male symbol and a female symbol; offspring symbols are connected in a row (sibship line) beneath the mated pair.

Detailed explanation-4: -On a pedigree, carriers are represented either by a half-shaded symbol or a shaded dot in the middle of the symbol.

Detailed explanation-5: -An affected male must have inherited the disease allele from his mother. An affected male must pass the disease allele to his daughter. A male never passes an x-linked trait to a son. An unaffected male cannot be a carrier and cannot transmit a disease allele to any child.