Exam 7: Sex Determination and Sex Chromosomes

A cross is made between a female calico cat and a male cat having the gene for black fur on his X chromosome.What fraction of the offspring would one expect to be calico?

Which of the following statements below is false?

In Drosophila,an individual female fly was observed to be of the XXY chromosome complement normal autosomal complement and to have white eyes as contrasted with the normal red eye color of wild type. -The female's mother and father had red eyes.The mother,however,was heterozygous for the gene for white eyes.Knowing that white eyes are X- linked and recessive,present an explanation for the genetic and chromosomal constitution of the XXY,white- eyed individual.

Data produced by C.Bridges in the early part of this century indicate that sex in Drosophila is determined by__________ .

Glucose- 6- phosphate dehydrogenase G6PD deficiency is inherited as an X- linked recessive gene in humans.A woman whose father suffered from G6PD marries a normal man.What percentage of their sons is expected to be G6PD?