What does the Hardy-Weinberg equation state about the frequency of alleles in a population?

The Hardy-Weinberg equation is a fundamental principle in population genetics that describes how allele frequencies in a population remain constant from generation to generation under certain ideal conditions, such as no mutation, random mating, no gene flow, infinite population size, and no selection. The equation specifically provides a mathematical framework to understand these frequencies.

The correct statement from the Hardy-Weinberg principle is that the sum of the frequencies of the two alleles in a population equals one. This is represented as p + q = 1, where p is the frequency of one allele and q is the frequency of the other allele. This indicates that the total proportion of alleles in a population must equal 100%, as any allele in a population can either be one type or the other.

In contrast, the other equations provided represent different aspects of the Hardy-Weinberg model. For example, p^2 + 2pq + q^2 = 1 describes the expected genotype frequencies based on the allele frequencies in the population. In this arrangement, p^2 represents the homozygous dominant genotype frequency, 2pq represents the heterozygous genotype frequency, and q^2 represents the homozygous recessive genotype frequency, which all together must equal one