Exam 25: Population and Evolutionary Genetics

Why are some proteins more likely than others to diverge within a species?

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?

Mutations are regarded as a strong evolutionary mechanism for changing allelic frequencies.

Which would change allele frequencies more quickly: selection against a dominant allele or selection against a recessive allele?

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

Provide a general definition for the term speciation.

What are the genetic consequences of inbreeding?

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

Inbreeding by itself can change gene frequencies.

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

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

Why is mitochondrial DNA often used in construction of phylogenetic trees?

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

Which term is given to the measure of the proportion of offspring that a particular phenotype will contribute to the next generation?

Define the term fitness and relate it to the meaning of selection coefficient.

What are phylogenetic trees?

Contrast directional and stabilizing forms of selection.

Assuming that p = 0.3 for a population in Hardy-Weinberg equilibrium,what would be the expected frequency of heterozygotes for the involved allelic pair?

Cytochrome c is a respiratory pigment found in the mitochondria of eukaryotes.Compared with some other proteins,it has changed very slowly over long periods of time.Why?