AP BIOLOGY

Detailed explanation-1: -Solution : Male sex in man and Drosophila is called hemizygous for sex linked genes because males have only one X-chromosome and only one allele of sex-linked character.

Detailed explanation-2: -Describes an individual who has only one member of a chromosome pair or chromosome segment rather than the usual two. Hemizygosity is often used to describe X-linked genes in males who have only one X chromosome.

Detailed explanation-3: -Generally, it manifests only in males. A male with an affected allele on his single X chromosome is hemizygous and can not transmit the disorder to their male offsprings, but all his daughters would be obligate carriers.

Detailed explanation-4: -Males are said to be hemizygous because they have only one allele for any X-linked characteristic; males will exhibit the trait of any gene on the X-chromosome regardless of dominance and recessiveness. Most sex-linked traits are actually X-linked, such as eye color in Drosophila or color blindness in humans.

Detailed explanation-5: -By the nature of X-chromosome-linked patterns of inheritance, females can be either homozygous or heterozygous for X-chromosome-linked traits, whereas males, because they have only a single X chromosome, are hemizygous.