The way we combine genes.
Aa should be =pq
Then why the equation is made=p?+2pq+q??
The Hardy-Weinberg Law states (using a formula p2 + 2pq+q2) an equilibrium of allele frequencies in a gene pool remains in effect in each succeeding generation of a sexually reproducing population if five conditions are met. They are random mating and the absence of mutation, gene flow, genetic drift and selection. But allele frequencies may change from one generation to the next, resulting in evolution. The Hardy-Weinberg law explains the factors that cause evolution. Hardy-Weinberg equilibrium states the constancy of gene pool frequencies that remains across generations.
In other words,
It is a mathematical concept which relates genotypes to allele frequencies. This principle helps to predict how gene frequencies will be inherited from one generation to the others, in a given set of conditions. It states that in a large population which breeds randomly allelic frquencies will reamin same, taking an assumption that there is no chance of mutation, selection etc. It is very important as it gives a measure to changes occuring in allele frquencies in a population.
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