GENERAL ECOLOGY EXAM 4
December 2003
Multiple choice. 2 points each
1. A bird that eats plant-eating insects occupies what trophic level?
a) 1st
b) 2nd
c) 3rd
d) 4th
2. The 2nd energy law
a) is the law of conservation of energy.
b) involves matter rather than energy.
c) contends that energy cannot be changed.
d) concerns the production of heat.
3. If 1000 Calories of energy are stored in tissues of organisms on the 2nd trophic level, how many of
these Calories may eventually find their way into tissues of organisms on the 4th trophic level?
a) 1
b) 10
c) 100
d) 1000
4. An ecosystem consists of
a) plants.
c) the abiotic environment.
b) animals.
d) all of the above
5. In communities, energy
a) increases at higher trophic levels.
c) cycles.
b) is first dispersed, but then is condensed and reused.
d) must constantly be replaced.
6. Within an ecosystem, most matter
a) cycles within the ecosystem.
c) is lost to the atmosphere.
b) is exported out of the ecosystem.
d) none of the above
7. What is the major role of decomposers in an ecosystem?
a) increasing entropy
b) recycling of energy back into the ecosystem
c) recycling matter back into the ecosystem
d) photosynthesis
8. The hydrologic cycle involves the movement of
a) carbon.
b) nitrogen.
c) water.
d) phosphorus.
9. Which of the following is an example of a sedimentary biogeochemical cycle?
a) carbon
b) nitrogen
c) water
d) phosphorus
10. What types of plants harbor nitrogen-fixing organisms within root nodules?
a) legumes
b) mosses
c) palms
d) gymnosperms
11. What single process is most important for getting carbon from the atmosphere into living organisms?
a) respiration
b) photosynthesis
c) erosion
d) precipitation
12. The current world fertility rate is
a) higher in developed countries than in developing nations.
b) above the ZPG replacement level fertility rate.
c) lower than the fertility rate in the United States.
d) significantly higher than the fertility rates in Kenya and Rwanda.
13. The dodo bird was driven to extinction by
a) elephants.
b) pigs.
c) wolves.
d) chimpanzees.
14. The species approach to conserving wildlife includes
a) developing captive breeding programs.
b) establishing wildlife refuges.
c) passing laws to protect threatened species.
d) all of the above
15. Phosphate
a) must be modified by soil bacteria before it can be used by plants.
b) is water-soluble.
c) can only be handled by certain bacteria because of its molecular structure.
d) none of the above
16. What organisms have been most harmed by exploitation?
a) zebra mussels
b) dodo birds
c) whales
d) California condors
17. What biogeochemical cycles are driven primarily by physical processes (mark all that are correct)?
a) hydrological cycle
b) nitrogen cycle
c) carbon cycle
d) phosphorus cycle
18. What organisms have been most harmed by commercial hunting?
a) zebra mussels
b) whales
c) California condors
d) dodo birds
19. The ecosystem approach to conserving wildlife includes
a) the establishment of biosphere reserves.
b) developing captive rearing programs.
c) agreeing to trade restrictions for furs, skins, and other body parts.
d) maintaining gene banks.
20. Secondary productivity
a) is lower than primary productivity in ecosystems.
b) is the rate of production of new biomass (stored energy) by consumers.
c) includes decomposers, too.
d) all of the above
21. Which biogeochemical cycles are driven primarily by physical processes? (mark all that are correct)
a) hydrologic cycle
b) nitrogen cycle
c) carbon cycle
d) phosphorus cycle
22. How do extinction rates today compare to "natural" rates from the past?
a) 10 times higher
b) 100-1000 times higher
c) 10 times lower
23. Nitrogen fixation
a) increases soil phosphate levels.
b) results in the loss of nitrogen from the soil back to the atmosphere.
c) is performed by bacteria in most systems.
d) all of the above
24. What is the current world human population size?
a) between 200 and 300 million
b) between 1 and 2 billion
c) over 6 billion
d) over 10 billion
d) the same
25. Which of the following is not an important greenhouse gas?
a) carbon dioxide
b) nitrogen
c) methane
d) CFCs
26. Phosphate is lost from ecosystems
a) because it is water-soluble.
c) through bacterial activities.
b) during respiration by decomposers.
d) when plants take it in during growth periods.
27. Primary production is highest in
a) tundras.
b) grasslands. c) forests
d) deserts
28. In what form is nitrogen most often taken up from the soil by plants?
a) nitrogen gas
b) ammonia
c) nitrite
d) nitrate
29. Which of the following is not a gaseous biogeochemical cycle?
a) phosphorus
b) nitrogen
c) carbon
d) all of the above are gaseous
30. Ecologically, what is the best way to deal with the impacts of acid rain on a sensitive lake ecosystem?
a) Restock the lake with fish.
b) Apply lime to the lake to neutralize the acid.
c) Give up and let eutrophication proceed.
d) Eliminate the air pollutants responsible for causing the acid rain.
31. What human activity has most impacted the California condor?
a) species introductions
b) habitat disruption
c) overexploitation
d) none of the above
32. What term describes the presence of unique species found nowhere else?
a) extinction
b) biodiversity c) polyploidy
d) endemism
33. What factors increase a species’ vulnerability to extinction?
a) small local popoulation
b) narow habitat range (habitat specialist)
c) small geographic range
d) all of the above
34. Which of the following are designated Biosphere Reserves (mark all that apply)?
a) Lake Park, Winona
b) Great Smoky Mountain National Park
c) Yellowstone National Park
d) Winona State University campus
35. By eating plant materials rather than animals as foods, how much more potential energy would be
available for human consumption?
a) 2 times more
b) 10 times more
c) 50 times more
d) 100 times more
36. What level of human sewage treatment currently is not required of municipalities like Winona?
a) primary
b) secondary c) tertiary
d) They are all required.
37. What groups of plants today are most threatened by extinction (two answers-mark both)?
a) gymnosperms
c) mosses
b) palms
d) apples
38. What group of organisms are zebra mussels expected to have the most severe impact on within the
upper Mississippi River?
a) waterfowl
b) native mussels
c) humans
d) fish
39. Increased fatalities of bald eagles on roads near Flathead Lake, Montana, were the indirect result of
a) DDT accumulation causing behavior changes.
b) introduction of opossum shrimp to the lake.
c) too few grizzly bears.
d) decreased snowmobile use in Yellowstone National Park.
40. Ecology is
a) the study of the interactions of plants and animals with each other and with their physical environment.
True or False. Mark A for true and B for false. 2 points each
41. The City of Winona spreads processed human sewage sludge on farmlands around Winona.
42. Inbreeding depression in very small populations increases the potential risk of extinction.
43. Acid rain is caused mostly by sulfur and nitrogen oxides.
44. Trees may die from acid rain mobilizing soil aluminum, damaging xylem tissues.
45. Colder regions are protected from acid rain, since snow cannot be acidic.
46. Soils based on the breakdown of granite and basalt have good acid-buffering abilities.
47. Habitat specialists with a small geographic range are especially vulnerable to extinction.
48. Chimpanzees are threatened mostly by habitat destruction.
49. Bald eagles nearly disappeared because DDT caused them to produce thin-shelled eggs.
50. Only certain bacteria can make use of atmospheric nitrogen.