Question

Which of the following is called Sewall Wright effect?

• A. Gene pool
• B. Gene flow
• C. Genetic drift
• D. Isolation

Answer 1

The correct option is C Genetic drift

Sewall Wright applied mathematical approaches to show the effect of finite population size on a different evolutionary genetic phenomenon. 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. He showed that the effect of genetic drift on a small population is large as compared to that on 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. Thus, genetic drift is also called as Sewall Wright effect.

All of the available alleles among the reproductive members of a population from which gametes can be drawn constitute its gene pool.

Gene flow refers to the movement of genes from one population to another by interbreeding between individuals of the two populations which in turn causes movement of genes from the gene pool of one population to that of other. Isolation refers to any barriers, physical/geographical, that prevent the gene flow between two populations.

So, the correct answer is option C.