Two heterozygous parents (Bb) have children. B is dominant over b. What is the probability that a child shows the recessive phenotype?
Answer and explanation
Correct answer: D. One in four
- Step 1: Each parent gives b with probability 1/2. Step 2. 1/2 x 1/2 = 1/4. Answer: one in four. Why not the others: these misread the cross.
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