AP BIOLOGY

Detailed explanation-1: -In the offspring of monohybrid crosses, or F2 generation, Mendel repeatedly observed a phenotype ratio of three plants with the dominant phenotype to one plant with the recessive phenotype (3:1) in the F2 generation.

Detailed explanation-2: -The F2 generation always produced a 3:1 ratio where the dominant trait is present three times as often as the recessive trait. Mendel coined two terms to describe the relationship of the two phenotypes based on the F1 and F2 phenotypes.

Detailed explanation-3: -When counting all four possible outcomes, there is a 3 in 4 probability of offspring having the yellow phenotype and a 1 in 4 probability of offspring having the green phenotype. This explains why the results of Mendel’s F2 generation occurred in a 3:1 phenotypic ratio.

Detailed explanation-4: -The normal phenotypic ratio in F2 generation is 3:1 and the genotypic ratio is 1:2:1.