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three different genes determine the coat colour of cats. one of the genes controls the black-based coat colour. there are three alleles for black-based coat colour genes with the following order of dominance: black (b) > chocolate (bch) > cinnamon (bc).

User Locksleyu
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Final answer:

Coat color in cats is a sex-linked trait carried on the X chromosome, resulting in black, yellow, or calico coats. Male cats cannot be calico because they have only one X chromosome. There is insufficient information to predict the exact phenotypes of the offspring from a yellow cat crossed with a black cat.

Step-by-step explanation:

Inheritance of Coat Color in Cats

The coat color in cats is determined by a gene located on the X chromosome. This type of inheritance is therefore sex-linked. Tortoiseshell cats exhibit a unique pattern of black and yellow patches due to the random inactivation of one of the two X chromosomes in each cell during embryonic development in females. This is a visible manifestation of X-chromosome inactivation, which is also known as lyonization. Since male cats have only one X chromosome, they do not show a tortoiseshell phenotype.

When considering the phenotypes of offspring from a cross between a yellow and a black cat, it's important to understand that yellow and black coat colors are due to different alleles on the X chromosome. In the case of crossing a yellow cat (which could be XX with yellow allele on each chromosome for a female, or XY with yellow allele on the X chromosome for a male) with a black cat (XX with black allele on each chromosome for a female, or XY with black allele for a male), the phenotypes of the offspring would depend on the sex and the combination of alleles they inherit. Due to the sex-linked nature of this trait, only females can be calico since they can inherit two different coat color alleles.

Without specific genetic information about the parents, we cannot determine the exact phenotypic ratio of the offspring, which makes option 'd' the correct answer for question number 38: There is not enough information to answer the question.

User Kurtanamo
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