IMAT Biology Practice Exam 2026 – Complete Study Resource

Gene flow involves the movement of alleles between populations through migration and interbreeding, so alleles from one population enter another and change allele frequencies in both groups. This is the description of the transfer of alleles between populations. It differs from mutation, which creates new alleles within a population, and from genetic drift, which is random fluctuation of allele frequencies in small populations. It also undermines the idea that migration blocks gene exchange; migration is what enables gene flow by carrying alleles across populations.