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?

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Calico cats are female cats that have patches of black, orange, and white fur. The gene for black fur is located on the X chromosome, and female cats have two X chromosomes. In order to be calico, a female cat must have one X chromosome with the gene for black fur and one X chromosome without the gene for black fur.In the cross between a female calico cat and a male cat with the gene for black fur on his X chromosome, the male cat will contribute an X chromosome with the gene for black fur to all of his offspring. The female cat will contribute an X chromosome with the gene for black fur to half of her offspring and an X chromosome without the gene for black fur to the other half of her offspring.Therefore, half of the offspring will be female and half will be male. Of the female offspring, half will be calico and half will be black. Therefore, one would expect 1/4 of the offspring to be calico.

A Cross Is Made Between a Female Calico Cat and a Male