AP BIOLOGY

Detailed explanation-1: -Genetic drift describes random fluctuations in the numbers of gene variants in a population. Genetic drift takes place when the occurrence of variant forms of a gene, called alleles, increases and decreases by chance over time. These variations in the presence of alleles are measured as changes in allele frequencies.

Detailed explanation-2: -Genetic drift is the change in the frequency of an allele in a population due to random sampling and the random events that influence the survival and reproduction of those individuals.

Detailed explanation-3: -So, while allele frequencies are almost certain to change in each generation, the amount of change due to sampling error decreases as the population size increases. Perhaps the most important point is that the direction of the change is unpredictable; allele frequencies will randomly increase and decrease over time.