Which symbol represents the frequency of the homozygous recessive genotype in the Hardy-Weinberg equation?

In the Hardy-Weinberg equation, the term that represents the frequency of the homozygous recessive genotype is denoted by q². The Hardy-Weinberg principle provides a mathematical model for predicting the genetic variation of a population at equilibrium.

In this equation, p represents the frequency of the dominant allele, q represents the frequency of the recessive allele, and the term q² specifically indicates the proportion of the population that exhibits the homozygous recessive genotype (aa). This is derived from the binomial expansion of (p + q)², which reveals that the frequency of the genotype can be predicted if the frequencies of the alleles are known. Therefore, q² accounts for the individuals that have two copies of the recessive allele, giving a clear representation of the frequency of that specific homozygous recessive trait in the population.