The expected phenotypic ratio of a dihybrid cross between two heterozygous parents (AaBb × AaBb) is
Answer and explanation
Correct answer: D. 9 : 3 : 3 : 1
- Step 1: Independent assortment of two genes gives 9 : 3 : 3 : 1.
Answer
9 : 3 : 3 : 1.
Why not the others: 3 : 1: this is the ratio for a monohybrid cross. 1 : 1 : 1 : 1: this is the ratio of a test cross of a dihybrid. 1 : 2 : 1: this is the genotypic ratio of a monohybrid cross.
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