ZOO 206 Study questions for Chapters 5 and 6 Evolutionary Analysis 4th ed 1 Describe in detail all of the sources of genetic variation give examples What are the types of mutations that offer the greatest potential for large changes in phenotypes Why 2 Describe two examples of how natural selection appears to favor one mutant allele or chromosome region over another For example in relation to latitude 2 Explain how the predisposition to undergo mutations can be favored by selection 3 What are the different ways in which we can determine if a particular gene has undergone a mutation 4 What are the general effects of mutations only no natural selection on the survival and reproduction of organisms Describe the evidence from C elegans as part of your answer 5 What is electrophoresis and what does it allow scientists to determine 6 What did investigators first predict they would find with regard to polymorphic loci when they first developed the technique of electrophoresis Why did they make that prediction 7 Describe the Hardy Weinberg Equilibrium HWE model and explain the assumptions upon which it is based How can the HWE model be used to determine whether the frequencies of two alleles or the frequencies of genotypes for a particular locus are changing over time 8 Be able to calculate what the frequencies of alleles should be for a locus with only two alleles as well as the proportion of different genotypes if the assumptions of the HWE hold MATERIAL FOR FIRST EXAM ENDS HERE 9 How can natural selection influence the frequencies of alleles and genotypes for a locus in a population If a population is subjected to natural selection does it necessarily cause a change in the frequency of alleles and genotypes 10 Describe the relationship between infection with HIV and the 32 CCR5 allele in human immune cells If the 32 CCR5 allele can exist at a frequency as high as 0 2 in some human populations e g Ashkenazi Jews why hasn t the allele increased in frequency in most human populations 11 For a locus that has only two alleles describe how selection is expected to act on a recessive allele that is lethal in the homozygous state as well as on the dominant allele Compare the frequencies of the two alleles above to what they would be if selection favored heterozygotes for the locus 12 Describe the various mechanisms by which loci can be maintained in a polymorphic state Give details of examples 13 If only mutation is affecting a population i e there is no recombination or any other forces affecting specific alleles say in a population of bacteria over many generations what is the outcome in terms of change in phenotype and fitness of various mutants Provide detailed evidence 14 Describe the evidence for why the frequency of the F508 allele of the cystic fibrosis transmembrane conductance regulator locus may be maintained at a rate higher than what a mutation selection balance would yield