Question : Assertion: Hardy-Weinberg principle explains the variations occurring in population and species over a number of generations. Reason: Hardy-Weinberg principle is applicable only when genetic drift occurs.

Question : Assertion: Hardy-Weinberg principle explains the variations

1.	Question : Assertion: Hardy-Weinberg principle explains the variations occurring in population and species over a number of generations. Reason: Hardy-Weinberg principle is applicable only when genetic drift occurs.
Answer» Solution :The relative frequencies of various kinds of genes in a large and randomly mating. Sexual panmictic population tend to remain constant from generation to generation in the absence of mutation, selection and GENE FLOW. This is called Hardy-Weinberg principle or Hardy-Weinberg equilibrium. It is RANDOM in gene (allele) frequency and occurs only by chance it is non-directional. Genetic drift can cause ELIMINATION of certain ALLELES or fixation of the other in the population leading to a change in the populatin of alleles in the gene pool so, genetic drift must not occur to maintain the equilibrium.