Kaplan Nursing Entrance Practice Exam

How do genotypes and phenotypes vary among individuals in a gene pool?

1. Each individual receives the same alleles

2. Each individual receives different sets of alleles

3. Individuals can only inherit dominant alleles

4. Allele distributions are random among individuals

The correct answer is: Each individual receives different sets of alleles

The correct choice emphasizes that each individual receives different sets of alleles, which contributes to the diversity of genotypes and phenotypes within a gene pool. This variation arises because individuals inherit a combination of alleles from their parents, meaning that even if parents share similar genetic backgrounds, the specific alleles passed down can differ. This genetic variation is crucial for the process of natural selection, as it provides a range of traits that can affect survivability and reproduction in changing environments. While it may seem intuitive to think that all individuals would inherit the same alleles, this is not the case in sexually reproducing populations. The mixing of alleles occurs during fertilization, leading to unique combinations in each offspring. This genetic diversity is vital for the adaptability and evolutionary potential of a species. The other choices do not accurately reflect the nature of genetic inheritance. Options indicating that all individuals receive the same alleles or can only inherit dominant alleles overlook the principle of genetic variation. Additionally, while allele distributions may involve random processes, the variety in combinations of alleles distinctly highlights the importance of this mechanism in contributing to the richness of phenotypes observed in any given population.