Unit N — Ecology

1. Which of the following is an abiotic feature of an environment?

A. Fish.
B. Birds.
C. Trees.
D. Rivers.

2. An organism’s (species’) niche is best described as the set of interactions between the organism and the

A. positive features of its environment.
B. abiotic parts of its environment.
C. abiotic and biotic parts of its environment.
D. positive and negative features of its environment.

3. Which of the following interactions occurs within a single species?

A. Parasitism.
B. Symbiosis.
C. Competition.
D. Predation.

4. Which of the following is descriptive of lichen?

A. Parasitism.
B. Symbiosis.
C. Competition.
D. Predation.

5. Which of the following would increase the size of a population?

A. Increased mortality.
B. Increased emigration.
C. Decreased immigration.
D. Increased natality.

6. A population of 1000 members is changing at the following rates: N = 10%, M = 14%, I = 18%, E = 22%. After one year, the population would be

A. 920.
B. 992.
C. 1008.
D. 1080.

7. Bacteria grown on agar in a Petri dish is an example of

A. carrying capacity.
B. closed population.
C. open population.
D. cyclical changes in population size.

8. When the density of a growing population surpasses the carrying capacity of its environment, the organisms will

A. stop reproducing until the population size degreases significantly.
B. reduce the number of offspring per female in the population.
C. begin to die faster than new ones are produced.
D. go extinct.

9. Cyclical changes in population density exist in an environment that is

A. relatively stable over a long period of time.
B. changing rapidly.
C. undergoing succession.
D. undergoing severe selective pressures.

10. In an energy pyramid, the producers are at the

A. top and there is more energy at each successive level.
B. top and there is less energy at each successive level.
C. bottom and there is more energy at each successive level.
D. bottom and there is less energy at each successive level.

11. Which of the following is LEAST likely to be true about herbivores and carnivores in the same ecosystem?

A. Both are part of the biota of the area.
B. The carnivores could prey on the herbivores.
C. They are both are the same trophic level.
D. The density of both populations undergoes regular fluctuations.

12. Which of the following is the BEST description of carrying capacity?

A. The maximum number of individuals a closed environment will support.
B. The maximum number of individuals a open environment will support.
C. The minimum number of individuals a closed environment will support.
D. The minimum number of individuals a open environment will support.

13. Which sequence is the most likely to occur during succession in a cedar forest?

A. Grasses deciduous trees cedar trees.
B. Cedar trees seedlings cedar trees.
C. Moss grasses deciduous growth.
D. Lichen shrubs and grasses trees.

14. A pioneer species is

A. an ancient type of organism.
B. one which has evolved quickly.
C. one which has avoided evolution.
D. one of the first types to grow in a new area.

15. Which kingdom does NOT contain photosynthetic organisms?

A. Plant.
B. Fungus.
C. Protist.
D. Monera (Eubacteria).

16. During photosynthesis, the products are

A. carbon dioxide and water, while the reactants are oxygen and sugar.
B. oxygen and carbon dioxide, while the reactants are sugar and water.
C. water and oxygen, while the reactants are sugar and carbon dioxide.
D. sugar and oxygen, while the reactants are carbon dioxide and water.

17. During cellular respiration, the products are

18. Organisms use sugar to make an energy-rich molecule called

A. TAP.
B. ATP.
C. PAT.
D. PTA.

19. Every population requires

A. a lack of predation.
B. continuous resources.
C. continuous succession.
D. inverted energy pyramids.

20. Extinction of one species in a stable ecosystem could do all of the following EXCEPT

A. go unnoticed.
B. cause the collapse of the ecosystem.
C. increase the interactions between the remaining species.
D. decrease the interactions between the remaining species.