What is the phenotypic ratio of a monohybrid cross between two heterozygous parents with complete dominance?
Answer and explanation
Correct answer: B. 3 : 1
- Step 1: Aa × Aa gives AA, Aa, Aa, aa, so three show the dominant trait for every one recessive. Answer: 3 : 1. Why not the others: 1 : 1, 1 : 2 : 1 and 9 : 3 : 3 : 1 don't fit.
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