ACC Biology Accuplacer Practice Test

The cross between F1 offspring of two individuals differing in two traits is referred to as a dihybrid cross. This method allows the examination of how two separate traits are inherited simultaneously. In a dihybrid cross, you would typically start with two parent strains that are homozygous for two different traits (e.g., seed color and seed shape), generating F1 offspring that are heterozygous for both traits. By crossing these F1 individuals, you observe the inheritance patterns of the two traits together, often resulting in a characteristic phenotypic ratio in the F2 generation, commonly 9:3:3:1 in a typical dihybrid cross. Monohybrid crosses focus on the inheritance of a single trait, which is not sufficient to describe the F1 offspring differing in two traits. Phenotype refers to the observable traits of an organism, while genotype denotes the genetic makeup, neither of which describes the process of crossing in this specific scenario. Thus, the term dihybrid cross correctly captures the genetic interaction being studied when two traits are involved.