Advanced Placement (AP) Biology Practice Exam

What genetic concept explains why blue-eyed and brown-eyed individuals can exist in the same population?

1. Phenotypic variation

2. Genetic diversity through independent assortment

3. Allelic dominance

4. Segregation of traits

The correct answer is: Genetic diversity through independent assortment

The correct answer highlights the role of genetic diversity through independent assortment, which is a fundamental principle in genetics. Independent assortment refers to the way that different genes independently separate from one another when reproductive cells develop. This means that the alleles for eye color can be inherited in various combinations. In a population where both blue-eyed and brown-eyed individuals exist, the diversity arises from the various alleles contributed by the parents during reproduction. These alleles, which may represent dominant or recessive traits, combine in different ways due to independent assortment, allowing for multiple phenotypes (such as different eye colors) to emerge within the same population. This principle is key to understanding how traits can be inherited and why variations in traits like eye color can coexist. Each individual's phenotype (observable characteristics) is a result of the specific combination of alleles inherited from their parents, highlighting the significance of genetic diversity in maintaining a variety of traits within a population.