In fruit flies, the gene for white eyes is sex-linked recessive. (R) is red and (r) is white. Cross a homozygous red-eyed female with a white-eyed male. Which of the following statements is true? *

A) 100% of the females will be white-eyed, and 100% of the males will be red-eyed.
B) 100% of the males will be white-eyed, and 100% of the females will be carriers.
C) 100% of the offspring will be red-eyed, and 100% of the female offspring will be carriers.
D) 50% of the females will be red-eyed, and 50% of the males will be white-eyed.

Where do the respiratory and circulatory systems meet? a. in the heart b. in the muscles c. in the lungs d. in the brain

Duchenne muscular dystrophy is a serious condition caused by a recessive allele of a gene on the human x chromosome. the patients have muscles that weaken over time because they have absent or decreased dystrophin, a muscle protein. they rarely live past their twenties. how likely is it for a woman to have this condition? a) women can never have this condition. b) one-fourth of the daughters of an affected man would have this condition. c) one-half of the daughters of an affected father and a carrier mother could have this condition. d) only if a woman is xxx could she have this condition.

10. in which phase will crossing-over occur? a. mitosis b. metaphase ii c. prophase i d. meiosis ii