Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. cats that have coats that are a patchwork of black and orange are called tortoiseshell cats, are typically female, and have genes that code for both black fur (xo) and orange fur (xo) located on the x chromosomes. y chromosomes do not code for color in tortoiseshell cats. a female cat that has only orange fur (xoxo) is crossed with a male cat that has only black fur (xoy).

Number of offspring’s that will have tortoiseshell coloring (XOXo) are  2

Explanation:

Key:  

A female cat that has only orange fur -> (xoxo)

A male cat that has only black fur -> (xoy)

So, as per the cross the four offspring’s would have the probability as follows

2 offspring’s: female cats that have have tortoiseshell coloring (XOXo)

2 offspring’s: male cats with orange coloring.

Cross:

Parents:                 XOXO       x        XoY

Offspring:       XOXo      XOY     XOXo    XOY

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