Nursing Entrance Exam (NEX) Practice Exam

Which process leads to genetic variation in a population?

1. Sexual reproduction

2. Asexual reproduction

3. Cell division

4. Mutation

The correct answer is: Sexual reproduction

Sexual reproduction is the process that leads to genetic variation in a population primarily because it involves the combination of genetic material from two parents. During sexual reproduction, each parent contributes half of their genetic information to the offspring through the processes of meiosis and fertilization. Meiosis generates gametes (sperm and egg cells) that carry different combinations of genes due to the processes of gene recombination and independent assortment. This mixing of genetic material is essential for introducing new genetic combinations into a population, which increases genetic diversity. Greater genetic variation allows populations to adapt to changing environments, enhance survival rates, and improve overall evolutionary success. While other processes such as mutation can also introduce genetic variation, sexual reproduction significantly amplifies the diversity generated by individual mutations, leading to a broader range of genetic combinations. Asexual reproduction, in contrast, typically produces genetically identical offspring, resulting in less variation. Cell division, depending on the context, is more about replication than introducing genetic diversity. Thus, sexual reproduction stands out as a key process for fostering genetic variation within a population.