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 frequency of an existing gene variant in the population due to random chance. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. It could also cause initially rare alleles to become much more frequent, and even fixed.

Detailed explanation-3: -The consequences of genetic drift are numerous. It leads to random changes in allele frequencies. Drift causes fixation of alleles through the loss of alleles or genotypes. Drift can lead to the fixation or loss of entire genotypes in clonal (asexual) organisms.

Detailed explanation-4: -Types of Genetic Drift Competition, disease, or predation leads to these massive decreases in population size. The allele pool is now determined by the organisms which did not die. Some alleles increase in frequency simply because they are the only alleles left.

Detailed explanation-5: -Answer and Explanation: The most common event that results from genetic drift is the population bottleneck which causes drastic changes in allele frequency in a very short period due to any random event.