In the term 2pq of the Hardy-Weinberg equation, why is the multiplication by two necessary? View Available Hint(s) In the term 2pq of the Hardy-Weinberg equation, why is the multiplication by two necessary? The term is multiplied by two because the effect of both the alleles is taken into account. There are two ways that a heterozygous individual can arise: either by receiving a recessive allele from the egg and a dominant allele from the sperm, or by receiving a dominant allele from the egg and a recessive allele from the sperm. The term is multiplied by two to account for doubling of the population in each generation. The frequency of the dominant allele is doubled because of its stronger effect on the phenotype.