BIO 304 Population Biology & Evolution-Exam 2

BIO 304 Population Biology & Evolution-Exam 2 here are 65 questions on 11 pages of this exam. 1. What was surprising about the results of Buri’s classic experiment on genetic drift in fruit flies (shown at right)? a. The flies showed no change in heterozygosity. b. Heterozygosity was maintained by mutation-selection balance. c. Strains maintained in benign conditions accumulated deleterious alleles. d. Heterozygosity declined more rapidly than predicted by Sewall Wright’s equation for the effects of genetic drift on heterozygosity. e. None of the above are true. 2. In the case study involving the phylogeny of whales, ________. a. molecular data and fossil data are in conflict with each other b. molecular data confirmed what was already known from the fossil record: whales are cetaceans c. fossil discoveries confirmed what molecular data already suggested: whales are cetaceans d. both molecular and fossil data are inconclusive 3. High mutation rates are thought to be most advantageous in _________________________. a. novel environments to which the organism is poorly adapted b. rapidly changing environments c. stable environments d. all of the above e. a and b, but not c f. b and c, but not a g. none of the above. 4. What are three essential components (“ingredients”) of maximum likelihood methods of phylogenetic analysis? a. mutation rate, fossil record, and radioactive decay b. branch lengths of the tree, bootstrapping, and convergence c. branch lengths of the tree, number of characters, and mode of DNA sequence evolution d. mode of DNA sequence evolution, branch lengths of the tree, and the tree e. none of the above 5. Sickle-cell anemia is caused by a mutation that substitutes the nucleotide thymine for adenine within a codon. This is an example of _________________________. a. a transition b. a transversion c. a silent site mutation d. a synonymous mutation e. gene duplication f. an inversion 6. Assortative mating is necessary for populations to achieve Hardy-Weinberg equlilibrium. a. True b. False 2nd Examination BIO 304 Population Biology & Evolution Page 2 of 11 2 7. Which of the following is NOT a condition necessary for Hardy-Weinberg equilibrium? a. Small population size b. No natural selection c. No migration d. Random mating e. No genetic drift 8. In a population of 1000 people, 250 had the AA genotype, 500 were Aa, and 250 were aa. What is the frequency of the a allele? a. .70 b. .60 c. .50 d. .30 e. .20 9. A point mutation at which position is least likely to cause a change in the amino acid coded for by a codon? a. 1st position b. 2nd position c. 3rd position d. 4th position 10. Offspring of first cousins have an inbreeding coefficient of ______. a. 1/2 b. 1/4 c. 1/8 d. 1/16 e. 1/32 11. Collared lizards in the Ozark Mountains are not affected by encroachment of oak-hickory and red cedar forests into their habitat. a. True b. False 12. Which of the following is NOT one of the types of variation that occurs among individuals? a. genetic variation b. environmental variation c. normalizing variation d. genotype-by-environment variation 13. Daphnia pulex grows protective armor upon sensing chemicals produced by the predatory phantom midge by the process of ________. a. barrier defense b. inducible defense c. stimulatory defense d. predatory defense 14. The patterns of phenotypes an individual may develop upon exposure to different environments is called its ________. a. predictability norm b. variability norm c. response norm d. reaction norm Freq AA= 250/1000=0.25= p2 , freq Aa = 5