UNIT 8: ECOLOGY TEST
(do not write on this test)
1. Herbivores are which of the following?
a. producers
b. secondary consumers
c. primary consumers
d. decomposers
2. Which phrase best describes biodiversity?
a. the number of individuals in an ecosystem
b. the amount of biomass in an ecosystem
c. the amount of available energy in an ecosystem
d. the number of species in an ecosystem
3. An ecologist counts weeds to monitor their populations. Which of the following best describes the ecologist's
methods?
a. modeling
c. experimentation
b. observation
d. hypothesizing
4. What do all the biotic and abiotic factors in a given area make up?
a. a habitat
b. a community
c. an ecosystem
d. a population
5. Which model shows the number of organisms at each trophic level in an ecosystem?
a. biomass pyramid
c. pyramid of numbers
b. food web
d. food chain
6. Which of the following provide most of the energy in ecosystems?
a. keystone species
b. carnivores
c. generalists
d. producers
7. Almost all autotrophs get their energy from
a. sunlight.
b. hydrothermal pools.
c. decaying matter.
d. producers.
8. The layer of air surrounding Earth is known as the
a. biosphere.
b. hydrosphere.
c. atmosphere.
d. geosphere.
9. Which of the following statements about the logistic model of population growth is incorrect?
a. It is influenced by density dependent factors.
b. It incorporates the concept of carrying capacity.
c. Most populations do not follow this model
d. It fits an S-shaped curve.
e. Limiting factors play a role in this population growth model.
10. Which of the following statements about energy flow is incorrect?
a. Producers have the most energy
b. Only about one-thousandth of the chemical energy fixed by photosynthesis reaches a tertiary-level
consumer.
c. Eating meat is probably the most economical way of acquiring the energy of photosynthetic
productivity.
d. About 90% of the energy at one trophic level does not appear at the next.
11. The producers in ecosystems include organisms in which of the following groups?
a.
fungi and bacteria
c.
plants
e.
A, B, and C
b.
algae
d.
B and C only
12 The most common kind of dispersion (population distribution) in nature is (think of wolves, humans)
a.
dispersive.
b.
clumped.
c.
even. d.
uniform.
e.
random.
13. Which two biomes have the least amount of precipitation?
a.
tundra and desert
c.
tropical rain forest and temperate grassland
b.
tiaga and chaparral
d.
tropical savanna and tropical dry forest
14. A population is correctly defined as having which of the following characteristics?
I.
inhabiting the same general area
II.
individuals belonging to the same species
III.
possessing a constant and uniform density and dispersion
a. III only
b. I and II only
c. II and III only
d. I only
e. I, II, and III
15. Carbon dioxide and other gases prevent some heat from escaping Earth's atmosphere. This is known as ____.
a.
photosynthesis.
c.
summer
e.
the carbon cycle
b.
global warming
d.
the greenhouse effect
16. As resources in a population become less available, population growth
a.
rapidly decrease immediately
d.
hits zero immediately
b.
reaches carrying capacity.
e.
increases slowly.
c.
enters a phase of exponential growth.
17. In general, the total biomass in a terrestrial ecosystem will be greatest for which trophic level?
a.
tertiary consumers
c.
primary producers
e.
secondary consumers
b.
primary consumers
d.
herbivores
18. An earthworm that feeds on the remains of plants and animals is acting as a
a.
primary consumer.
c.
tertiary consumer.
e.
detritivore.
b.
producer.
d.
secondary consumer.
19. You are most likely to observe primary succession when you visit a(n)
a.
a river.
d.
abandoned field.
b.
tropical rain forest.
e.
a volcanic island.
c.
a habitat destroyed by deforestation
The following questions (#20 and #21) refer to the figure below, which depicts the age structure of three
populations.
20. Which population appears to be stable?
a. III
b. II and III
c. II
d. I and II
e. I
21. Which population is in the process of decreasing?
a. II and III
b. I and II
c. III
d. I
e. II
22. A bird making its nest high in the branches of a tree is an example of
a.
commensalism.
c.
parasitism.
e.
b.
predation.
d.
symbiosis.
competition.
23. Polar regions are cooler than the equator because
a.
the poles have a thicker atmosphere.
b.
there is more ice at the poles.
c.
the poles are permanently tilted away from the sun.
d.
the poles are farther from the sun.
e.
sunlight strikes the poles at an oblique (large) angle.
24. Which of these terms applies to the relationship between a dog and a blood-sucking tick?
a.
commensalism
c.
mutualism
e.
competition
b.
parasitism
d.
predation
25. Important abiotic factors in ecosystems include which of the following?
a. temperature
b. plants
c. wind
and C
d. A and C only
e. A, B,
26. In a tide pool, 15 species of invertebrates were reduced to eight after one species was removed. The species
removed was likely a(n)
a.
parasite.
c.
dominant species.
e.
resource partitioner.
b.
mutualistic organism.
d.
keystone species.
27. Probably the most important factor(s) affecting the distribution of biomes is (are)
a.
day length and rainfall.
c.
climate and vegetation.
diversity.
b.
community succession.
d.
wind patterns.
e.
species
28. An increase in Earth’s average temperature from the buildup of carbon dioxide and other gases in the atmosphere
is called
a.
global warming (climate change).
c.
seasonal changes.
e.
the greenhouse
effect.
b.
Nitrification
d.
ozone depletion.
29. Evidence shows that some grasses benefit from being grazed (eaten). Which of the following terms would best
describe this plant-herbivore interaction?
a.
commensalism c.
parasitism
e.
competition
b.
predation
d.
mutualism
30. Dwarf mistletoes are flowering plants that grow on certain forest trees. They obtain nutrients and water from the
vascular tissues of the trees. The trees derive no known benefits from the dwarf mistletoes. Which of the following
best describes the interactions between dwarf mistletoes and trees?
a.
commensalism
c.
parasitism
e.
mutualism
b.
facilitation
d.
competition
31. Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?
a.
community, ecosystem, individual, population
b.
population, ecosystem, individual, community
c.
individual, community, population, ecosystem
d.
ecosystem, community, population, individual
e.
individual, population, community, ecosystem
32. Nitrifying bacteria participate in the nitrogen cycle mainly by
a.
converting nitrogen gas to ammonia to nitrate, which is absorbed by plants as fertilizers.
b.
incorporating nitrogen into amino acids and organic compounds.
c.
releasing ammonia from organic compounds, thus returning it to the soil.
d.
converting ammonia to nitrogen gas, which returns to the atmosphere.
The symbols +, –, and o are to be used to show the results of interactions between individuals and groups
of individuals in the examples that follow. The symbol + denotes a positive interaction, – denotes a
negative interaction, and o denotes where individuals are not affected by interacting. The first symbol
refers to the first organism mentioned.
33. What interactions exist between a tapeworm and a human?
A) +/+
B) +/o
C) +/–
D) o/o
E) –/–
34. What interactions exist between a bee and a flower?
A) +/+
B) +/o
C) +/–
D) o/o
E) –/–
35. About what percent of energy is available for the organisms at the next trophic level in an ecosystem?
a.
b.
c.
d.
90 %
25%
75%
10%
36. Which of the following parts of Figure 13.2 is an example of a
biotic factor?
a. sunlight
b. soil
c. deer
d. river
37. Based on these two graphs, what is the biggest difference
between the grassland and forest biomes?
a. annual precipitation
b. annual temperature
c. length of winter
d. hot grassland summers
38. Which of the following is a characteristic of tropical rain forests?
a. a distinct rainy season
b. few organisms living in trees
c. extreme heat fluctuations
d. thin soil that is low in nutrients
39. Which is NOT a keystone species
a. beavers.
b. wolves.
c. water hyacinth.
d. sea otters.
40. In which direction does energy flow through this energy pyramid to the right?
a. 4, 3, 2, 1
b. 1, 2, 3, 4
c. 2, 1, 3, 4
d. 3, 4, 2, 1
4
3
2
1
41. In the carbon cycle, through what process does carbon move from an abiotic resource into organic matter?
a. immigration
b. combustion
c. respiration
d. photosynthesis
42. ______________________ is all the resources that COULD be used by a population. What is this?
a. Fundamental Niche
b. Realized Niche
c. Logistic Niche
d. Exponential Niche
43. What happens in biomagnifications?
a. The energy is lost as you move up the trophic levels
b. The energy is gained as you move up the trophic levels
c. The toxins decrease as you move up the trophic levels
d. The toxins increase as you move up the trophic levels
44. Consider a field plot containing 200 kg of plant material (producer). Approximately how many kg of SECONDARY
consumer (carnivore) production can be supported?
a.
20
b.
200
c.
2
d.
10
e.
100
45. What element is the most abundant in the atmosphere?
a. Oxygen
b. Carbon
c.
d.
Hydrogen
Nitrogen
46. How is phosphorus different than the other common elements?
a. It isn’t as important
b. Animals do not use them
c.
d.
Plants do not use them
They are not found in the air
47. Why do organisms need nitrogen?
a. Provides short-term energy
b. To produce carbohydrates
c.
d.
To produce lipids
To produce proteins
48. The eutrophication that has taken place in the Gulf of Mexico and other locations appears to be due to
_______________.
a. global warming from human use of fossil fuels
b. pesticide use along the waterways
c. heavy metals dumped in the sewage
d. weather alone, because it is only obvious in the summer
e. excess nutrients from fertilizers
49. Which of the following is not true of a eutrophic lake?
a. low in nutrients
b. low in dissolved oxygen
c. water is not clear
d. accumulation of dead algae and detritus
e. suffocation of fish and shellfish
50. People fighting for food at a grocery store is an example of:
a. Predation
b. Parasitism
c. Interspecific competition
d. Intraspecific competition
51. If the density of chipmunks is 20 chipmunks per km2, how many chipmunks will there be in 200 km2?
a.
b.
c.
d.
2000 chipmunks
1000 chipmunks
3000 chipmunks
4000 chipmunks
52. Stress and diseases from population crowding is:
a. density-dependent factor
b. density-independent factor
c. nature-depending factor
d. none of the above
53. Refer to the graph above. What type of graph is this?
a. exponential graph
b. realized graph
c. logistic graph
d. fundamental graph
54. Refer to the graph above. What is marked as a?
a. log phase
b. lag phase
c. carrying capacity
d. environmental resistance
55. What is another name for exponential growth graph?
a. realistic graph
b. logistic graph
c. biotic potential
d. fundamental graph
Figure 1
56. Figure 1 shown above is an illustration of the ________________________ cycle.
a. phosphorus
b. hydrological (water)
c. nitrogen
d. carbon
57. Dead organic material is converted into nutrients that can be used by other organisms. What type of organisms
carry out this conversion?
a. decomposers
b. consumers
c. carnivores
d. producers
58. High concentrations of sediment in the water can block out sunlight needed by aquatic plants for photosynthesis.
This condition will most likely result in
a. increased concentration of nitrogen
b. decreased concentration of nitrogen
c. increased concentration of oxygen
d. decreased concentration of oxygen
59. The nonnative zebra mussel was first found in a lake near Detroit in 1988. By 1989, it had colonized all Great
Lakes waterways. Which scenario is most likely true regarding the introduction of this species?
a. Native fish naturally eat zebra mussels
b. The higher biodiversity leads to healthier lakes
c. They compete with native mussels for food and other resources
d. Native mussel populations are growing rapidly.
60. Which situation would most efficiently decrease the size of a field mouse population?
a. decreased death rates and emigration
b. decreased birth rates and immigration
c. decreased death rates and immigration
d. increased death rates and immigration
e. increased death rates and emigration
61. CO2 is important in our atmosphere because it is required for photosynthesis and it traps some heat, keeping Earth
warm. However, human-produced CO2 is a problem because it
a. leads to higher global temperatures
b. disrupts the natural cycling of other greenhouse gases
c. adds too much CO2 to the oceans
d. causes uncontrolled photosynthesis
62. Which of the following can contribute to density-dependent regulation of populations?
a.
intraspecific competition for nutrients
d.
disease
b.
the accumulation of toxic waste
e.
all of the above
c.
predation
THERE ARE MORE QUESTIONS ON THE BACK
Figure 3
63. Refer to Figure 3. If the herring population drops, the bald eagle is more likely to
a.
Eat more rats, salmon, and vole
b.
Eat more insects such as grasshoppers
c.
Switch to eating carrots and corn
d.
die out completely
64. Refer to Figure 3. In a given environment, which animal would most likely have the fewest numbers of individuals?
a. rat
b. salmon
c. snow geese
d. killer whale
65. Refer to Figure 3. Which of the following is NOT a predator of the mosquito?
a. Salmon
b. Herring
c. Rat
d. None of the above