Physiological Ecology, Bio 31 Final Exam, 1 June 2013 Name: 9 pts 1. Briefly define or identify each of the following terms. epistasis - Jensen s Inequality - science - 8 pts 2. Distinguish between the following terms by providing an illustrative, unambiguous example of each. Ancestral character - vs. Derived character - Acclimatization - vs. Adaptation - 4 pts 3. All organisms, in all lifestages, have biochemical pathways that allow the controlled release of energy from organic molecules. Why? 5 pts 4. On a global scale, where are the terrestrial ecosystems with the highest primary productivity? Why? 4 pts 5. Write the summary equation for photosynthesis. 3 pts 6. Why is the breast muscle of ducks dark meat while the breast muscle of ruffed grouse is white meat? page 1
5 pts 7. Is the transport of water from the soil to leaves an energetically demanding process for plants? (circle one) yes sometimes no Briefly explain 8 pts 8. The data below show diurnal patterns in atmospheric CO2 concentration measured at mid-canopy in a Wisconsin forest. Measurements were at 30 min intervals. Figure at left shows two days in July. Figure at right shows two days in October. Why does CO2 increase at night? Why does CO2 decrease during the day? Why does CO2 attain a higher maximum concentration in July than in October? Why does CO2 attain a lower minimum concentration in in July than in October? 4 pts 9. What are the two main products of foregut fermentation that benefit ruminants? What are the substrates that yield the products? 1. Substrate Product ))))))))))))))) )))))))))))))))))))))))) 2. page 2
6 pts 10. Populations of crop plants that have gone feral (i.e., escaped from cultivation to survive and reproduce in nature) almost always produce higher concentrations of secondary metabolites than their domestic counterparts. Offer a plausible hypothesis for why this may be true and suggest an experiment to test it. Hypothesis: Test: 5 pts 11. Draw two functions on the graph at right to indicate the partial pressure of oxygen in water and blood across the respiratory exchange surface of a trout. Label the lines Water and Blood. Draw an arrow next to each function indicating the direction of flow. 5 pts 12. As a result of human consumption of fossil fuels, atmospheric concentrations of CO2 are increasing, which in turn is tending to increase global temperatures. How would you expect these changes to influence competitive interactions between C3 and C4 plants? Explain your reasoning. 8 pts 13. A colleague down the hall has recently created a new plant mutant that produces 30% more RuBP carboxylase (rubisco) in its leaves, but otherwise seems to be identical. He wonders how the mutation could affect its physiological ecology. Help him out by sketching two functions on the adjacent plot (label "wild type" and "mutant") Explain your reasoning. Describe an environment in which this mutant might have an ecological advantage over the wild type. page 3
6 pts 14. State three possible (all-inclusive) explanations for why an organism does not occur in some habitat or region? 1. 2. 3. 4 pts 15. Why do the most valuable furs tend to come from mammals that are of medium size? 6 pts 16. State the essential postulates of the theory of evolution by natural selection. 10 pts 17. Draw two functions in each of the graphs below representing a 20 g roadunner (a bird, beep-beep ) and a 20 g lizard living in the same high desert environment. Label the lines roadunner and lizard. 6 pts 18. Mary Lou Guerinot has discovered a plant mutation that increases the density of carrier proteins in the cell membranes nd of fine roots. Draw a 2 function on the adjacent graph indicating how you would expect nutrient uptake kinetics to be influenced by this mutation. Under what conditions could such a mutation be beneficial to the plant. Explain? page 4
8 pts 19. Answer one of the following questions drawn from departmental seminars during the term. A. From the results of Laurel Symes, how does the species richness of Oecanthus tree crickets influence the evolution of tree cricket mating behavior? B. Identify a prominent hypothesis from the work of Sam Fey about how climate change could influence the future distribution of the invasive Cladoceran, Daphnia lumholtzi. C. How did Eric Warrant test whether dung beetles orient with respect to the Milky Way? 6 pts 20. Give an example of a specific theoretical principle from physiological ecology that can contribute to a scientific discipline or human endeavor outside the traditional domain of physiological ecology. Briefly explain the relevance. Theoretical principle - Scientific discipline or human endeavor - Relevance of principle - 6 pts 21. Recently developed technology, known as free atmospheric carbon enrichment (FACE), permits experimental studies of increasing CO2 on whole ecosystems. Some of the first results have just been reported. Over 4 years, pine stands exposed to 700 ppm of CO2 were compared to matched stands that experienced ambient CO2 of about 350 ppm. Enriched stands did not have higher primary productivity (which was surprising to many scientists because increased CO2 increases photosynthesis when individual branches or leaves are treated) but did have much higher soil respiration rates. Suggest plausible explanations for these two results. Explanation for lack of increase in primary productivity - Explanation for increased soil respiration - page 5
12 pts 22. Fence lizards (Sceloporus undulatus), which are the most northerly distributed species of lizard in North America, occur from Georgia to southeastern New York state. Sprint speed at relatively cool temperatures (e.g., 20 C) could be a factor influencing lizard success in northerly climes. Describe an experiment that would test for (1) genetic variation in among populations in sprint speed at 20 C, (2) adaptive phenotypic plasticity in sprint speed at 20 C, and (3) genetic variation in phenotypic plasticity of sprint speed at 20 C. Show possible results that would indicate each of the following scenarios: A. 1 but not 2 or 3 B. 2 but not 1 or 3 C. 1, 2, and 3 Brief description of experiment Scenario A Scenario B Scenario C 12 pts 23. Identify a research topic in Physiological Ecology that would be a candidate for a highly successful Ph.D. program during the next 5 years or so. An organizing question - Study system and technical approach - Significance of the research for Biology - page 6