Answered

The Hardy-Weinberg equation is shown below:

[tex]\[ p^2 + 2pq + q^2 = 1 \][/tex]

If [tex]\( q \)[/tex] is the frequency of the recessive allele, what does [tex]\( q^2 \)[/tex] represent in the equation?

A. The frequency of the homozygous dominant genotype
B. The frequency of the heterozygous genotype
C. The frequency of the homozygous recessive genotype
D. The frequency of the gene in the population



Answer :

To determine what [tex]\( q^2 \)[/tex] represents in the Hardy-Weinberg equation, we first need to understand the components of the equation:

[tex]\[ p^2 + 2pq + q^2 = 1 \][/tex]

Here:
- [tex]\( p \)[/tex] represents the frequency of the dominant allele in the population.
- [tex]\( q \)[/tex] represents the frequency of the recessive allele in the population.

Given that [tex]\( p \)[/tex] and [tex]\( q \)[/tex] are the frequencies of the dominant and recessive alleles respectively, each term in the equation corresponds to the different genotypes possible in a population:

1. [tex]\( p^2 \)[/tex]: This term represents the frequency of individuals who are homozygous dominant (have two dominant alleles).
2. [tex]\( 2pq \)[/tex]: This term represents the frequency of individuals who are heterozygous (have one dominant allele and one recessive allele).
3. [tex]\( q^2 \)[/tex]: This term represents the frequency of individuals who are homozygous recessive (have two recessive alleles).

So, in the context of the equation, [tex]\( q^2 \)[/tex] specifically denotes the frequency of the homozygous recessive genotype in the population. Thus, among the given options:

A. The frequency of the homozygous dominant genotype — incorrect
B. The frequency of the heterozygous genotype — incorrect
C. The frequency of the homozygous recessive genotype — correct
D. The frequency of the gene in the population — incorrect

Therefore, the correct answer is:
C. The frequency of the homozygous recessive genotype.