Which of the following is a true statement concerning genetic variation?
A) It is created by the direct action of natural selection.
B) It arises in response to changes in the environment.
C) It must be present in a population before natural selection can act upon the population.
D) It tends to be reduced by the processes involved when diploid organisms produce gametes.
E) A population that has a higher average heterozygosity has less genetic variation than one with a lower average heterozygosity.

Question

Quizplus · Accepted Answer

Genetic variation must be present in a population before natural selection can act on it. Without genetic variation, there would be no differences in traits for natural selection to act upon.

Answer: D
 The processes of meiosis and fertilization during sexual reproduction can result in a reduction in genetic variation, as the number of possible allele combinations is lowered. This is known as genetic drift.

Note: Choice E is false. A higher average heterozygosity indicates a greater diversity of alleles and therefore a higher level of genetic variation.

Which of the Following Is a True Statement Concerning Genetic