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 Ecology Multiple Choice Questions


Bio-geochemical Cycles 
Quiz I

Problem set I

Ecology Test 
Test 1   Test 2
Test 3   Test 4
Test 5   Test 6
Test 7   Test 8
Test 9   M/C 

Energy Calculation 
Quiz 1   Quiz 2

Human Ecology  
Quiz 1   Quiz 2
Quiz 3   

Population Dynamics 
Quiz 1   Quiz 2
Quiz 3   Quiz 4
Quiz 5   Quiz 6

1 .   Many individuals of the same species living together in a  defined area form a/an 

     a .   community.

     b .   genus. 

     c .   *correct*population.

     d .   ecosystem.

     e .   variety.

  2 .      Biological communities change because 

     a .   *correct*each stage modifies the environment and adapts for a later stage.

     b .   the soil is depleted and food gives out.

     c .   old species move out and new species move in.

     d .   old species evolve into new species.

     e .   new species move in, displacing old species. 

3 .    When two different species overlap in the same biological niche, they are 

     a .   unaffected by one another.

     b .   dependent on one another.

     c .   in co‑operation with one another.

     d .   *correct*in competition with one another.

     e .   dependent on different food supplies. 

4 .      Consider the following list of factors:

          I     dispersal

          II     rainfall

          III     mineral deposits

          IV     competition

          V     temperature. 

     Which of the factors listed above are most significant in determining the fact that belts of vegetation at successively higher altitudes often correspond to those at successively higher latitudes? 

     a .   I and III

     b .   III and V

     c .   II and IV

     d .   *correct*II and V

     e .   I and V 

5 .      Which of the following is characteristic of parasitism? 

     a .   One organism kills and consumes another.

     b .   Two organisms live together and neither is harmed.

     c .   Two organisms feed side by side from the same food.

     d .   Two organisms nourish each other; both benefit.

     e .   *correct*One organism lives in or on another and benefits. 

6 .      Which of the following terms best describes the inter- relationship between nitrogen‑fixing bacteria and the clover in whose roots they live? 

     a .   *correct*mutualism

     b .   commensalism

     c .   predation

     d .   parasitism

     e .   amensalism

  7 .    The progressive series of changes that eventually produce a climax community on what was once a bare rocky island is an example of 

     a .   *correct*primary succession.

     b .   speciation.

     c .   secondary succession.

     d .   evolution.

     e .   eutrophication. 

8 .    Some water, a small amount of soil, a few green aquatic plants and a fish were placed in a large bottle. The bottle was sealed to prevent the exchange of gases and other materials between its contents and the outside.  The bottle was placed in a window to receive light during the daytime.  Is carbon dioxide produced by the plants?

      a .   Yes, but it is produced only at night when the plants can no longer carry on photosynthesis.

     b .   *correct*Yes, it is produced all the time as a result of cellular respiration.

     c .   No, it is a waste product of animals only.

     d .   No, plants take in only the waste products exhaled by animals.

     e .   No, plants only produce oxygen. 

9 .      During the growth of a tomato plant from a seed, it increases considerably in biomass.  Which of the following  materials, obtained from the environment, are necessary for the growth and increase in biomass?

     a .   carbon dioxide and water

     b .   carbon dioxide, oxygen, and nitrogen

     c .   water, nitrate, and methane

     d .   *correct*water, carbon dioxide, and mineral salts

     e .   mineral salts, carbon dioxide, and oxygen 

10 .      Nitrogen gas returns to the atmosphere by the action of 

     a .   nitrogen fixing bacteria.

     b .   *correct*denitrifying bacteria.

     c .   nitrifying bacteria.

     d .   nitrate fertilizers.

     e .   ammonia. 

11 .   A molecule of nitrogen which you have just breathed in may  have been part of a plant that lived thousands of years ago, or part of a dinosaur that lived millions of years ago.  This illustrates the principle that 

     a .   dead organisms may be fossilized.

     b .   molecules of cytoplasm may be replaced by inorganic salts.

     c .   nitrogen does not combine readily with other elements.

     d .   *correct*decay bacteria cycle elements.

     e .   nitrogen forms part of the proteins of plants and animals. 

12 .   The sequence of energy flow through a food chain is 

     a .   primary consumers‑ producers‑ higher order consumers.

     b .   producers‑ higher order consumers‑ primary consumers.

     c .   higher order consumers‑ primary consumers‑ producers.

     d .   primary consumers‑ higher order consumers‑ producers.

     e .   *correct*producers‑ primary consumers‑ higher order consumers. 

13 .   In a terrestrial ecosystem, the trophic level that would contain the largest biomass would be the 

     a .   *correct*producers.

     b .   primary consumers.

     c .   secondary consumers.

     d .   highest order consumers.

     e .   decomposers. 

14 .   A carrot plant is exposed to carbon dioxide containing  radioactive carbon for 24 hours.  After this exposure, the carrot roots are found to have accumulated radioactivity. These carrots are then fed to a rabbit.  One week later, the rabbit's tissue is tested for radioactivity and is found  to have a higher than normal background count.   Which biogeochemical cycle is apparent from this study? 

     a .   oxygen

     b .   mineral

     c .   water

     d .   *correct*carbon

     e .   nitrogen

   15 .   The rate of growth of a natural population 

     a .   always reaches the carrying capacity of the ecosystem.

     b .   *correct*is limited by the carrying capacity of the ecosystem.

     c .   when graphed, always has a positive slope.

     d .   is calculated by subtracting death rate from birth rate.

     e .   exceeds the death rate and rate of emigration. 

16 .   In the past decade, which of the following has NOT been a major cause of the increase in the world's population?

      a .   longer life span

     b .   lower infant mortality

     c .   *correct*increase in birth rate

     d .   improved sanitation

     e .     modern preventative medicine