Question

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).
How many of the offspring will exhibit tortoiseshell coloring?
1 in 4
2 in 4
3 in 4
4 in 4

Answer 1

THE ANSWER IS 2 IN 4

Of total 4 offspring, 2 female cats that have tortoiseshell coloring (XOXo), and 2 male cats with orange coloring.

Answer 2

Answer:

The correct answer would be 2 in 4.

According to the question Xo and XO show codominance and express themselves completely when present in heterozygous condition. Cats bearing XoXO show patchwork of black and orange fur and are called tortoiseshell cats.

Xo codes for orange color fur and XO codes for black color fur. In addition, Y chromosome does not contain any gene associated with fur color.

Now, genotype of mother cat is XOXO (orange fur). So, the gametes formed would be XO only.

The genotype of father cat is XoY(black fur). So, the gametes would be Xo and Y.

The cross would lead to the formation of two male cats each having XOY as their genotype and two female cats each with XOXo as their genotype.

Hence, both the male cats would show orange fur and both the female cats would show patchwork of orange and black fur.

Therefore, we can conclude that 2 out of 4 would exhibit tortoiseshell coloring.