Evolutionary processes Chapter 25 Flashcards
Describe the four processes that can change allele frequencies in populations.
Use the Hardy-Weinberg principle to test whether evolution or non-random mating is occurring at a particular gene.
Discuss the four types of natural selection.
Discuss the influence of genetic drift.
Predict the results of inbreeding and non-random (assortative) mating on a population.
Discuss the influence of sexual selection on the evolution of traits.
In general terms describe how natural selection, genetic drift, gene flow, and mutations alter allele frequencies in populations (Freeman p 477).
What is the gene pool imagined by Hardy and Weinberg?
If just two alleles of a particular gene exist in a population (A1 and A2), their frequencies are given by p and q. Provide the three genotypes that are possible, and the mathematical formula that represents the genotype frequencies.
Given a parental generation allele frequency of A1: p = 0.6 and A2: q = 0.4, use a Punnett square to calculate the genotype frequencies and allele frequencies in the offspring generation in a population where no evolution is occurring with respect to gene A.
List the five assumptions that must be met for a population to conform to the Hardy-Weinberg principle.
How does the Hardy-Weinberg principle serve as a null hypothesis?
With reference to Case Study 1 (Freeman p 480), is the human population presently undergoing evolution with respect to the MN blood type gene? Why or why not?
With reference to Case Study 2 (Freeman p 481), is the Havasupai human population in Arizona presently undergoing evolution with respect to the HLA-A and HLA-B genes? Why or why not?
Differentiate between the four types of natural selection: directional selection, stabilizing selection, disruptive selection, and balancing selection.
