Exam 22: Population and Evolutionary Genetics

Would one expect a linear relationship between DNA sequence divergence and phylogenetic distance? Why or why not?

In large random mating populations, random genetic drift is usually a significant factor in changing gene frequencies.

List and briefly describe three factors that contribute to the phenomenon of natural selection.

The difference between fitness of a given genotype and another genotype considered optimal is called the selection coefficient (s). What is the selection coefficient for a genotype (aa) that produces an average of 99 offspring when Aa individuals produce an average of 100 offspring?

Which term is given to the total genetic information carried by all members of a population?

In a population of 10,000 individuals, in which 3600 are MM, 1600 are NN, and 4800 are MN, what are the frequencies of the M alleles and the N alleles?

In zoo animals, inbreeding often occurs because of a lack of a sufficient pool of breeding individuals. Under such conditions, which two characteristics are often exhibited among inbred organisms?

Why might mitochondrial DNA be used in construction of phylogenetic trees rather than nuclear DNA?

What is meant by the equation p + q = 1.0?

Inbreeding by itself can change gene frequencies.

In directional selection, both phenotypic extremes are equally selected against.

For a given locus, in a population with two alternative alleles, the allele frequencies p + q = 1.0.

List at least five of the assumptions that pertain to a population in a Hardy -Weinberg equilibrium.

In a population of 100 individuals, 49 percent are of the NN blood type. What percentage is expected to be MN assuming Hardy -Weinberg equilibrium conditions?

Evolution is dependent on genetic diversity in the evolving population.

Mutation and migration introduce new alleles into populations. What is the most likely principal force that will shift allelic frequencies within large populations?

In an evolutionary sense, what is meant by the term molecular clock?

In the case of complete dominance in a population in equilibrium, we cannot tell which individuals are homozygous dominants and which are heterozygous, but by knowing the frequency of the homozygous recessives, we can estimate the frequency of homozygous dominant and heterozygous genotypes.

One of the Hardy -Weinberg assumptions states that the population is infinitely large. What influence might a small population size have on a Hardy -Weinberg equilibrium?

What are phylogenetic trees?