How can genetic variation occur within a population?

Genetic variation within a population can arise through several mechanisms, and the correct choice acknowledges multiple processes that contribute to this diversity.

Mutations are random changes in the DNA sequence that can result in new alleles. These mutations can occur spontaneously during DNA replication or can be induced by environmental factors. They are a crucial source of genetic variation because they create new genetic material that can be passed on to future generations.

Gene flow refers to the transfer of alleles from one population to another through mechanisms like migration. When individuals move between populations and breed, they introduce new genetic material into the gene pool, which increases genetic diversity in the recipient population.

Sexual reproduction contributes to genetic variation through the combination of genetic material from two parents. During meiosis, the process by which gametes are formed, independent assortment and crossing over lead to a shuffling of alleles, resulting in offspring that have different combinations of genes compared to their parents.

By encompassing mutations, gene flow, and sexual reproduction, this choice effectively illustrates the various ways in which genetic variation can arise, reflecting the complexity of evolutionary processes and the importance of genetic diversity in populations for adaptability and survival.