When a population is in Hardy-Weinberg equilibrium, which of the following statements is true?

• A. Genetic drift leads to a loss of genetic variation.
• B. Natural selection causes allele frequencies to change rapidly.
• C. Allele and genotype frequencies remain constant from generation to generation.
• D. Mutations occur at a high rate, altering allele frequencies each generation.

Answer: (C)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of Hardy-Weinberg equilibrium. It is a principle stating that allele and genotype frequencies in a population remain constant from generation to generation in the absence of evolutionary influences.
2. Step 2: Identify the conditions required for Hardy-Weinberg equilibrium to hold true. These include: no mutations, random mating, no natural selection, extremely large population size (to prevent genetic drift), and no migration (gene flow).
3. Step 3: Analyze each statement provided in the problem and compare it to the conditions of Hardy-Weinberg equilibrium. For example, genetic drift, natural selection, and high mutation rates are evolutionary forces that disrupt equilibrium.
4. Step 4: Focus on the correct statement: 'Allele and genotype frequencies remain constant from generation to generation.' This aligns with the definition of Hardy-Weinberg equilibrium, as it describes the population in a stable state without evolutionary influences.
5. Step 5: Conclude that the other statements are incorrect because they describe processes (genetic drift, natural selection, and mutations) that would disrupt Hardy-Weinberg equilibrium by altering allele frequencies.