Posted by Whitney on .
In cats the allele B produces black, whereas b produces yellow. Neither gene is dominant, and in the heterozygous state the phenotype is a combination of yellow and black spots called tortoise-shell. The alleles B and b are “X-Linked”. If a tortoise-shell cat has three tortoise-shell kittens and two black kittens, give the genotype and phenotype of the tomcat that produced them, and give the sex of the kittens.