Question

Consider mendel's pea plants in which a single gene determines whether the peas are yellow from the dominant allele y or green from the recessive allele y (when both alleles are y). according to the hardy-weinberg principle of equilibrium, what is the frequency of heterozygous individuals in a population under low selective pressure?

Answer 1

If a single gene Y determinates the colour of the peas than:

YY is dominant homozygous genotype-yellow phenotype

Yy is heterozygous genotype-yellow phenotype

Yy is recessive homozygous genotype-green phenotype.

Hardy-Weinberg equation: p2 + 2pq + q2 = 1, where

p2 is the frequency of dominant homozygous genotype,

2pq is the frequency of heterozygous genotype and

q2 is frequency of recessive homozygous genotype.