What does the Hardy-Weinberg equation for allele frequencies state?

The Hardy-Weinberg equation for allele frequencies is expressed as p + q = 1. In this equation, p represents the frequency of one allele (usually the dominant allele), while q represents the frequency of the alternate allele (usually the recessive allele) in a given population. This equation highlights the principle that, in a population that meets the assumptions of Hardy-Weinberg equilibrium (large size, random mating, no mutation, no migration, and no selection), the frequencies of the two alleles must add up to 1.

Understanding this equation is crucial because it provides a baseline expectation for the distribution of alleles in a population. If the sum of the allele frequencies deviates from 1 in a specific population, it might indicate that one or more of the Hardy-Weinberg assumptions are not being met, which can lead to changes in allele frequencies over time due to evolutionary processes.

The other expressions mentioned in the options represent additional aspects of the Hardy-Weinberg principle but do not directly state the basic relationship of allele frequencies. For example, p² + 2pq + q² = 1 defines the expected genotype frequencies based on allele frequencies, while the other options are incorrect formulations that do not reflect the fundamental relationship