In cat, the gene for black coat is dominant to the gene for white coat. A heterozygous black cat is crossed with a white cat. which of the following is true about the ratio of the offspring from the cross?

Black coat, White coat
A. 1,3
B. 3,1
C.4,1
D.4,0
can you please give me an explanation for this question. thanks in advance.

The first sentence is wrong. White is not a color in cats. It embarrasses me that you were told that.

http://ib.berkeley.edu/courses/ib162/Week3a.htm
http://en.wikipedia.org/wiki/Cat_coat_genetics
http://kids.cfa.org/understanding-cat-colors.pdf

well thanks for the info. but how do i answer this question.

In this case, the black coat color is dominant, and the white coat color is recessive. The heterozygous black cat would have the genotype Bb, where B represents the black coat gene and b represents the white coat gene. On the other hand, the white cat would have the genotype bb.

When these two cats are crossed, their offspring will inherit one gene from each parent.

Possible genotypes of the offspring:
- BB: black coat
- Bb: black coat
- bB: black coat
- bb: white coat

By analyzing the genotypes, we can determine the phenotypes (coat colors) of the offspring. From the possible genotypes, we can see that the ratio of black coat to white coat is:

3 black coat : 1 white coat

Therefore, the correct answer is B. 3,1.

To determine the ratio of the offspring from the cross, we need to understand how the genes for coat color are inherited. In this scenario, black coat color is dominant over white coat color. Let's break down the cross to understand how the genes are passed on.

We have a heterozygous black cat (Bb) crossed with a white cat (bb). The dominant gene for black coat color is represented by "B," and the recessive gene for white coat color is represented by "b."

When we cross these two cats, we can determine the possible genotypes and phenotypes of the offspring using a Punnett square.

The Punnett square for this cross would look like this:

| B | b |
--------|-------|-------|
b | Bb | bb |
--------|-------|-------|

From the Punnett square, we can see the possible genotypes and phenotypes of the offspring. There are two possible genotypes: Bb (black coat) and bb (white coat).

The ratio of the offspring genotypes is 1:1 because there is only one Bb genotype (black coat) and one bb genotype (white coat).

Therefore, the ratio of offspring with a black coat to offspring with a white coat is 1:1.

Thus, the correct answer is:

Black coat : White coat = 1:1