1. Why do gene frequencies in a population change? Why don't they stay the same from one generation to the next? Explain how the processes of mutation, crossover, and natural selection can provide an answer to these questions.
Support your response with cited documentation where appropriate.© BrainMass Inc. brainmass.com October 9, 2019, 8:44 pm ad1c9bdddf
Consider the example of Hardy-Weinberg equilibrium provided as an attachment.
The population has a slight deviation from Hardy-Weinberg equilibrium in the above case as p2+2pq+q2=0.98 instead of 1.0.This situation of disequilibria might be the result of small population size, migration and selective forces which favor or hinder the expression of certain phenotypes. It can also occur due to non-random mating. Here, the slight variation might also be due to polygenic effects of genes, wherein different loci additionally affect a particular trait. At times, it may be due to the existence of lethal alleles present in a population, as a result of which, most recessive alleles, be it lethal or not, are not expressed in every generation; instead, they will be ...
The situation of disequilibria or deviation from Hardy-Weinberg equilibrium might be the result of small population size, migration and selective forces which favor or hinder the expression of certain phenotypes. It can also occur due to non-random mating.