Question

When one refers to a population being in Hardy-Weinberg equilibrium, the total number of genes and their alleles in the population is:

• A. Always constant
• B. Variable
• C. Constant only at certain conditions
• D. Can not be determined

Answer 1

The correct option is A Always constant

When one refers to the population in Hardy-Weinberg equilibrium, the total number of genes and their alleles in a population remains constant. According to the principle, if a population is large and randomly mating and evolutionary forces are absent, then the allele frequencies in a population remain stable and constant from one generation to the next.

In the expression p + q = 1, where p and q stand for frequencies of dominant and recessive alleles in the population, its binomial expansion is expressed as $p^2+2\mathrm{pq}+q^2=1$,
where $p^2$ is the genotypic frequency of homozygous dominant, 2pq is the frequency of heterozygous, and
$q^2$ is the frequency of homozygous recessive individuals in a population.