Question

The maximum effect of genetic drift is seen in

• A. A small, isolated population
• B. A large, isolated population
• C. Two widespread, interbreeding populations
• D. Two geographically isolated, large populations
• E. Two isolated, interbreeding populations

Answer 1

The correct option is A A small, isolated population

Genetic drift is a change in gene frequency in successive generation of a small population due to chance alone rather than natural selection or gene transfer. The effect of genetic drift on a small population is large as compared to that in the larger population which, owing to its large size and a large number of gametes produced, has a greater probability to accurately represent the allelic frequency of a parental population. Isolated populations do not exhibit gene flow and have the maximum effect of genetic drift. Thus, the correct answer is option A.