Question

Black fur(B) in guinea pigs is dominant over white fur(b). Find the probability of a white offspring in a cross: Bb x bb.

A. 0%
B. 25%
C. 50%
D. 75%
E. 100%

Answer 1

Using a Punnett square to analyze the cross Bb x bb in guinea pigs, the probability of producing a white offspring (bb) is 50%.

Step-by-step explanation:

To determine the probability of a white offspring in a cross between a guinea pig with black fur (Bb) and a white fur guinea pig (bb), we can use a Punnett square. The Punnett square illustrates how alleles combine from each parent. For the cross Bb x bb, we place B and b from the first parent across the top and both b's from the second parent down the left side. We then draw the possible genotypes for the offspring by combining the alleles from each parent.

Here's the Punnett square:

• Column 1: B from the top, b from the side - Bb (black fur)
• Column 2: b from the top, b from the side - bb (white fur)

As we can see, half the offspring will be Bb (black fur) and the other half will be bb (white fur). Therefore, the probability of a white offspring (bb) is 50%.