The Two Figures Represent an Asexual and a Sexual Population

question 3

Multiple Choice

The two figures represent an asexual and a sexual population. The letters indicate beneficial mutations. The shaded areas represent the frequency of particular combinations of mutations in the population over time. Why does it take longer for the beneficial allele combination of ABC to go to fixation in the asexual population than in the sexual population?

• A) In the asexual population, new allelic combinations have to arise via de novo mutations.
• B) There is no principal difference between asexual and sexual populations. In the sexual population shown, the favorable mutations just happen to be on different chromosomes.
• C) The effective population size of both populations is the same.
• D) Sexual populations tend to have higher mutation rates.

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Definitions:

Vernix Caseosa

A white creamy biofilm covering the skin of the fetus during the last trimester of pregnancy, protecting the newborn's skin.

Lanugo

Fine, soft, unpigmented fetal hair.

Colostrum

Thin, white fluid; the first milk secreted by the breast at the termination of pregnancy; contains less fat and lactose than the milk secreted later.

Fetal Hair

Also known as lanugo, it is the fine, soft hair that covers the body of a fetus as a form of insulation.