Question

which of the following statements about genetic drift and population size is true

A) if a population is large enough, it will not experience any genetic drift

B) the larger a sample is, the less likely it is similar to its source population

C) A population is unlikely to lose genetic diversity when its size is drastically reduced

D) the effects of genetic drift are more pronounced in very small populations

Answer 1

The correct answer is option D. Genetic drift is the change of allelic frequency in a population over time. It is also called allelic drift. It occurs at random. Genetic drift occur in all populations, regardless of their size. But the effect of genetic drift will be more in smaller populations. This is because their gene pool is small, thus are more likely to be affected with random changes. Option A is wrong, because both small and large populations are effected by genetic drift. Option B is not correct. A sample is the representation of the source population from which it is taken.Sample size will be always smaller than the source population. In large samples, it will be similar to the source population. Because the sample size is high, thus it contain most of the representations of the source population. Option C is wrong, because, when the population size is reduced it will lose the genetic diversity.When population size is reduced more chance to lose some genes due to randome chances, because ther gene pool is smaller. Thus the genetic diversity will be reduced, and there is chance for extinction.