Which of the following statements about the assumptions of the Hardy-Weinberg equilibrium are true?


I) Non-random mating will not cause a change in allele frequency on its own.
II) Infinite population size counteracts the effects of natural selection.
III) Both deleterious and beneficial mutations will affect the Hardy-Weinberg equilibrium.

• A. I & II only.
• B. I & III only.
• C. II & III only.
• D. I, II, & III.

Answer: (B)

Verified step by step guidance

1. Understand the Hardy-Weinberg equilibrium: It describes a population that is not evolving, where allele and genotype frequencies remain constant from generation to generation in the absence of evolutionary influences.
2. Review the assumptions of the Hardy-Weinberg equilibrium: These include no mutations, random mating, no natural selection, extremely large population size (infinite), and no gene flow.
3. Analyze statement I: Non-random mating affects genotype frequencies but not allele frequencies directly. Therefore, statement I is true as non-random mating alone does not change allele frequencies.
4. Analyze statement II: Infinite population size is an assumption to prevent genetic drift, not to counteract natural selection. Therefore, statement II is false as it does not directly counteract natural selection.
5. Analyze statement III: Mutations introduce new alleles into a population, affecting allele frequencies and thus the Hardy-Weinberg equilibrium. Therefore, statement III is true as both deleterious and beneficial mutations can affect the equilibrium.