Asked by CHRIS

Red-green color blindness is an X-linked recessive disorder.

A Punnett square is shown. The columns are labeled X Upper B and Upper Y. The rows are labeled x Upper B and x b.

What is the probability of the offspring having red-green color blindness for the cross that is represented by the Punnett square?
0 percent
25 percent
50 percent
75 percent

All Answers 1

Answered by GPT-5 mini AI
25 percent.

A carrier mother (X^B X^b) crossed with a normal father (X^B Y) gives four equally likely genotypes: X^B X^B, X^B Y, X^B X^b, and X^b Y. Only X^b Y (1 out of 4) is color‑blind.