X-Linked Inheritance

Color blindness is a recessive X-linked trait in humans. In a family where the XX mother is heterozygous for color blindness and the XY father is color-blind, the probability of their having a color-blind XX offspring is: A. 1/4 B. 1 C. 1/16 D. 0 E 1/2

A. 1/4

In humans, fruit flies, and many other organisms, most of the genes on the X chromosome are not found on the Y chromosome. A. true B. false

A. true

For most genes on the human X chromosome, what percent of XY males with a mutant allele on the X chromosome will express the mutant phenotype? A. there is insufficient data to predict B. 100% C. 0% D. 25% E. 50%

B. 100%

If an XY male carries a mutation on his X chromosome, ________ will receive the mutant X. A. all of his sons B. all of his daughters C. half his sons and half his daughters D. all his sons and daughters

B. all of his daughters

Color blindness is a recessive X-linked trait in humans. In a family where the XX mother is color-blind and the XY father is wild type, the probability of their having a color-blind XY offspring is: A. 1/16 B. 3/4 C. 0 D. 1/2 E. 1

D. 1/2

A normal female who carries a recessive X-linked allele for hemophilia will pass it on to: A. half of her daughters B. half of her sons C. all of her daughters D. all of her sons E. half of both her sons and daughters

E. half of both her sons and daughters