Q1 Explain the function of retroposition (retroduplication) in gene duplication. Describe the cellular mechanism used for this method of gene duplication, and the manner in which these typically nonfunctional pseudogenes can become active, functional genes.
Q2 Explain the relationship between genotype and phenotype with respect to the ability in humans to taste phenylthiocarbamide (PTC), and the correlation of this ability to the type 2 taste receptors (TAS2Rs). How does the conformation of the TASTRs receptors affect the ability to sense the bitter taste of phenylthiocarbamide?
Q3 Honey bees demonstrate morphological variations depending on the division of labor among the various morphotypes. Worker bees are quite different morphologically from the queens, who are different from the drones. Can you comment on which type of variation this might be, and the basis behind this variation?
Q4 What are reaction norms, and why do they matter? Draw your own reaction norm for mood as a function of the temperature outside. What kind of variation allows reaction norms to evolve?
Q5 Organisms that exhibit different phenotypes in different environments are said to exhibit pheno- typic plasticity. Using the tobacco hornworm, Manduca sexta, studied by Suzuki and Nijhout, describe the experiments done to illustrate the dependence of color on temperature. Be sure to explain the importance of using reaction norms in this type of study.
Q6 Chromosome inversions often have a major impact on evolutionary processes. Describe the process and causes whereby chromosome inversions occur. Describe the effect chromosome in- versions have on the process of meiosis, and provide a specific example of chromosome inversions discussed in the text.
Q7 Compare and contrast the evolutionary roles of point mutations, chromosome inversions, gene duplications, and polyploidization.