Name: _________Key______________ CE 210 Sample Third Exam Fall 20xx Closed Note Portion B.A. DeVantier Matching. (2 points each) Put the letter of the description on the right which best describes one of the terms on the left. No letter may be used more than once. _E_ Log growth phase A. First stage of batch microbial culture concentration curve. _G_ Desert biomes B. Earth land regions of biotic systems existing only in northern hemisphere. _I_ Stationary phase C. Biome change due only to direct human action. _J_ Freshwater biomes D. Earth regions in which life has adapted to ocean salinity. _L_ Death phase E. Second stage of batch microbial culture concentration curve. _D_ Marine biomes F. Earth land regions with biodiversity but very few trees. _K_ Desertification G. Earth regions in which life has adapted to conserve water and moderate heat. _A_ Lag phase H. Earth land regions with biodiversity, many trees, and at higher elevations. _C_ Deforestation I. Third stage of batch microbial culture concentration curve. _H_ Taiga biomes J. Earth regions in which life has adapted to water without ocean salinity. _M_ Soil erosion K. Biome change due to creep into grasslands. _N_ Rain forest biomes L. Fourth stage of batch microbial culture concentration curve. _O_ Decelerating growth M. Ecosystem threat increased by agricultural practices. _F_ Grassland biomes N. Earth land regions with high biodiversity, high precipitation and many trees. _B_ Tundra biomes O. Last part of second stage of batch microbial culture concentration curve. Multiple Choice. (3 points each) Circle the letter of the phrase which best completes each sentence below. 1. Microbe weight (or mass) is dominated by A. elemental carbon. B. water. C. elemental oxygen. D. elemental nitrogen.2. The highest elemental microbe mass contribution considered “trace” (not nitrogen) is A. phosphorus. B. calcium. C. magnesium. D. iron. 3. The batch microbial growth segment occurring after substrate is depleted is A. lag phase. B. log growth phase. C. stationary phase. D. death phase. 4. Exponential growth of a microbial culture will occur so long as A. there is more than enough substrate. B. there are more than enough trace nutrients. C. waste products have not built up to high levels. D. all of the above. 5. Increasing a microbial culture’s temperature somewhat should result in A. an increase in doubling time. B. transition to death phase. C. an increase in pH. D. an increased growth rate constant. 6. Decelerating growth in a microbial culture A. occurs because of substrate buildup. B. occurs because of nutrient buildup. C. occurs as substrate is depleted. D. is the same thing as death phase. 7. Biomes are A. are geographic components of ecosystems. B. ecosystems. C. the biosphere. D. all of the above. 8. Coral reefs are classified as A. freshwater biomes. B. marine biomes. C. taiga biomes. D. wetlands. 9. Ponds and lakes are classified as A. freshwater biomes. B. marine biomes. C. taiga biomes. D. wetlands.10. Desert biomes are most importantly characterized by A. high biodiversity. B. brackish soils. C. low annual precipitation. D. all of the above. 11. Rainforest biomes are most importantly characterized by A. high biodiversity. B. brackish soils. C. low annual precipitation. D. all of the above. 12. Tundra biomes A. cover Antarctica. B. have low biotic diversity. C. are near the equator. D. are also known as taiga. 13. Grassland biomes A. can appear as savannahs. B. can appear as temperate grasslands. C. can exist in warmer and colder climates. D. all of the above. 14. Deforestation leads to biodiversity loss, because A. organisms protected by tree cover must move. B. carbon sequestration starves the organisms. C. soils become so dry that only organisms adapted to low water can survive. D. water cannot drain because it is frozen much of the year. 15. Desertification leads to biodiversity loss, because A. organisms protected by tree cover must move. B. carbon sequestration starves the organisms. C. soils become so dry that only organisms adapted to low water can survive. D. water cannot drain because it is frozen much of the year.Name: _______________________ CE 210 Third Exam Spring 2011 Open Note Portion B.A. DeVantier Problem 1 (15 points) A batch culture of microbes has an initial concentration of 0.01 million organisms per mL. After 2 hours and 5 hours, the respective concentrations have increased to 0.08 and 0.25 million organisms per mL respectively. Using a plot of ln N/N0 versus time, determine the growth rate constant and then the doubling time.Problem 2 (10 points) Given that a dried mass of living matter has the following percentages of the four larges elements: C H N O 48% 9% 18% 25% Give a chemical formula with nitrogen having one as its subscript. Subscripts with tenths such as 1.1 are