AP Biologyeasymcq1 pt
What is the phenotypic ratio of a dihybrid cross (AaBb × AaBb) for two unlinked genes with complete dominance?
A.9:3:3:1
B.3:1
C.1:1:1:1
D.9:7
Explanation
Core Concept
Independent assortment multiplies the two 3:1 ratios: (3:1)² = 9:3:3:1 for dominant-dominant, dominant-recessive, recessive-dominant, and double recessive.
Correct Answer
A9:3:3:1
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