In the dihybrid cross AaBb × aabb,what proportion of individuals are expected to be homozygotic for both genes in the F₁ generation? A) 1/4 B) 1/2 C) 3/4 D) All are homozygotes. E) None are homozygotes.

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In a dihybrid cross, the F1 generation will be heterozygous for both genes. Therefore, the cross is AaBb × aabb. When we make the Punnett square for this cross, we get the following: | | A | a | B | b | |---|---|---|---|---| | a | Aa| aa| Ab| ab| | a | Aa| aa| Ab| ab| | b | aB| ab| aB| ab| | b | aB| ab| aB| ab| From this Punnett square, we can see that there are four different possible genotypes in the F₁ generation that are homozygous for both genes (AABB, AaBB, aaBB, and AAbb), out of a total of 16 possible genotypes. Therefore, the proportion of individuals in the F₁ generation that are homozygous for both genes is 4/16 or 1/4.

In the Dihybrid Cross AaBb × Aabb,what Proportion of Individuals