Define Hardy-Weinberg's Principle. What is the significance of this principle?

Explanation

Hardy-Weinberg Principle. Hardy-Weinberg principle says that the allele frequency in a population are stable and is constant from generation to generation, called as genetic equilibrium.
The gene pool (total genes and their alleles in a population) remain constant. This is called genetic equilibrium. The frequency of all the alleles is 1. Individual frequencies are p, q etc. In a diploid organism, p and a represent the frequency of allele A and allele a. The frequency of AA in a population is simply `p^(2)`. Similarly of aa is `q^(2)`, of Aa is 2pq. Hence `p^(2)+2pq +q^(2)=1`. This is a binomial expansion of `(p+q)^(2)`.
Factors Affecting Hardy-Weinberg Equilbrium.
1. Gene migration or gene flow.
2. Genetic drift
3. Mutation
4. Genetic recombination
5. Natural selection
Significance.
1. The difference between measured frequency and its expected values indicates the extent of evolutionary change.
2. Disturbance in genetic equilibrium i.e., change of frequency of alleles in a population results in evolution.