Ecology Review Page 2


1. The nitrogen cycle consists of these processes:

a) nitrification -- oxidation of ammonia in the soil to nitrite and nitrate

b) nitrogen fixation -- reduction of atmospheric nitrogen (N2) into ammonia

c) denitrification -- removal of nitrogen from ammonia and converting it to N2 gas

d) ammonification -- decomposition of organic compounds like protein into ammonia

2. A good-tasting prey species may defend against predation by using Batesian mimicry wherein it mimics an unpalatable or harmful model

3. All organisms capable of fixing nitrogen belong to the Kingdom Monera.

4. An ecosystem consists of a community and its physical environment.

5. Insects that have evolved to closely resemble twigs will probably be able to avoid which of the following: competition, parasitism, or predation. __________________

6. A(n) small island would be expected to have low species diversity.

7. Aposematic coloration protects a species by _______________________________________

8. Bacteria are important for processes other than decomposition in the nitrogen cycle.

9. Biogeochemical cycles are global (covering the entire earth) for elements that are found in the atmosphere which include water, carbon (CO2), and atmospheric nitrogen .

10. The producers in ecosystems include the following three kingdoms:

a) cyanobacteria in the kingdom Monera .

b) algae in the kingdom Protista and

c) plants

11. Carbon cycles relatively rapidly except when it is stored in wood or fossil fuels such as petroleum, and ____________,

12. Compared to the open ocean, marine life is especially abundant and diverse near the shore because inorganic ____________ are more plentiful near the shore.

13. Detritivores in ecosystems include which two groups? bacteria and ______________

14. Ecologists use mathematical models and computer simulations because these approaches allow them to study the interactions of variables and simulate large-scale experiments.

15. Evolutionary history:

a) influences the distribution of organisms.

b) involves the cumulative effects of the interactions between organisms and their environment .

c) has produced the adaptations of organisms to different environments.

16. Give a biotic factor which could cause a realized niche to differ from a fundamental niche? ______________________

17. In general, the total biomass in a terrestrial ecosystem will be greatest for which trophic level? Producers

18. In the nitrogen cycle, the bacteria in the soil or root nodules of legumes that reduce atmospheric nitrogen to ammonia are Rhizobium bacteria

19. List three terrestrial biomes which are adapted to frequent fires?

a) ___________________

b) ____________________

c) ____________________

20. Name the biome which is able to support many large animals despite receiving only moderate amounts of rainfall? Savanna

21. Net primary productivity may be described as __________________________ minus energy used by the producers for cellular respiration.

22. Resource partitioning involves slight variations in available niches which allow closely related species to coexist.

23. The most important role of decomposers is to recycle molecules back to ____________.

24. The mottled coloring of peppered moths living in the unpolluted regions of England would be an example of cryptic coloration or camouflage .

25. The organisms which can fix nitrogen in aquatic ecosystems are the cyanobacteria originally called the blue green algae

26. The ability of some herbivores (the larva of the Monarch butterfly ) to eat plants that have toxic secondary compounds may be an example of - coevolution .

27. The ample rainfall of the tropics and the arid (desert) areas around 30o north and south latitudes are caused by the global circulation of air initiated by intense direct sunlight near the equator producing wet and warm air.

28. Biomes with the shortest growing season are tundra and tiaga .

29. A highly successful parasite will be able to feed without killing its host.

30. The ecological unit which incorporates abiotic factors is called a(n) ecosystem .

31. An ecosystem which accounts for the largest amount of Earth's primary productivity is the open ocean - photic zone .

32. The greenhouse effect: may result in an increase in temperature when CO2 absorbs more heat which would normally escape into space. This could change global weather and lead to the _____________________ of coastal areas.

33. The high concentrations of DDT and other fat soluble pesticides found in birds of prey is an example of biological magnification .

34. The permafrost of the arctic tundra froms a layer of solid ice most of the year which helps to keep the soil from getting wet since water cannot soak in. This in turn prevents plant roots from penetrating very far into the soil, which restricts plants to low-growing forms.

35. List three desert animal adaptations to low amounts of water and high temperatures

a) living in burrows (underground) and estivating

b) the ability to excrete uric acid rather than urea

c) being active only during the night (nocturnal)

36. The principle of competitive exclustion states that two species cannot indefinitely occupy the same niche if resources are limited?

37. The rate at which solar energy is converted to the chemical energy of organic compounds by autotrophs is termed gross primary productivity .

38. Small crustaceans having a variable internal salt concentration, which changes with the salt concentration of its external environment are examples of osmo-conformers .

39. Terrestrial biomes are usually identified by their: plant associations

40. The species richness of a community refers to the number of different species found in a community. Species diversity considers two numerical components of populations within a community: species richness and relative abundance.

41. The sum total of an organism's use of the biotic and _____________ resources of its environment is called its niche .

42. The taxonomic similarity of species within biogeographic realms is mostly a reflection of the past history of species' distributions.

43. The traditional concept of succession includes the idea of an equilibrium state called a climax community. Ecologists now think there may be no such thing as a climax community because _________________ is ongoing in ecosystems.

44. An example of the effects of removing a keystone predator might be the reduction of 15 species of herbivores to only eight.

45. Where would you most likely find marine phytoplankton? photic or euphotic zone

46. The increasing diversity of the benthic community with depth may be an example of a cline that may be related to increasing environmental stability.

47. Which trophic level, are fungi typical of? decomposers

48. Primary succession occurs where no soil is present in an area. Some examples are: _______________________, glaciation, and inundation by sterile sand

49. When the environment of an animal changes, the animal may respond in several ways. List a probable sequence (from most rapid to slowest) of potential animal responses using the follwing terms: acclimation, evolution, migration, and morphological change

a) migration

b) acclimation

c) morphological change

d) evolution

50. Circle which of the following are considered autogenic factors in succession?

a) early colonizers that shade other species
b) accumulation of humus from decomposition
c) periodic fires that restart secondary succession
d) changes in soil pH from accumulated tannins that make soil unsuitable for present inhabitants