State Hardy-Weinberg equilibrium and mention the factors affecting the equilibrium of a population.

Explanation

Allele frequencies in a population are stable and are constant from generation to generation .OR
Allele frequency or gene frequency in a population (gene pool) remains constant from generation to generation unless there are factors to upset it .
Role of factors that affect Hardy -Weinberg equilibrium :
Gene flow : It is the movement of genes or alleles from one population to another when there is a migration of a section of population to another place and population . This changes gene frequencies .
Genetic drift : It is the random change in the gene frequency by chance (in small populations ) The change in gene frequency in the new population may be so different that the members become a different species (founder.s effect ) .
Mutation : It is the sudden heritable change in genetic material which results in new genotypes adn phenotypes , thus altering the gene frequency .
Genetic recombination : It occurs during gametogenesis (meiosis ) and results in variations . This would result in change in gene frquency over a period of time .
Natural selection : Variations that occur as a result of mutations or recombinations or due to gene flow or genetic drift enhance reproductive success or fitness . Survivors would leave more progeny and overa period of time the gene frequency of the population changes.