Download EcoTest 3 Practice

ECOLOGY!
PRACTICE QUESTIONS – EXAM 3
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1. Among lakes, primary productivity seems to be
mainly controlled by levels of
6. Which statement about Nile perch in Lake Victoria is
A) light. B) nutrients. C) temperature.
most likely true?
D) pollutants. E) none of the above
A) Nile perch are native to Lake Victoria.
B) Introduction of Nile perch to Lake Victoria
increased fish diversity in the lake.
2. In most ecological communities, we find
C) Introduction of Nile perch to Lake Victoria
A) more rare species than moderately common or
wiped out all native fish species in the lake.
very common ones.
D) Introduction of Nile perch to Lake Victoria
B) more very common species than
immediately decreased fish diversity in the lake.
moderatelycommon or rare ones.
E) Introduction of Nile perch to Lake Victoria
C) more moderately common species than rare or
decreased fish diversity in the lake, but only
very common ones.
after many years of no apparent effect.
D) roughly equal proportions of rare, moderately
common, and very common species.
E) no rare species ñ apparently ìrareî species are
7. Ant-acacia trees provide several services to their
artifacts of incomplete sampling.
mutualistic ant partners. These include
A) enlarged thorns to host ant colonies.
B) nectar from foliar nectaries.
3. Cleaner wrasse are mutualists of other coral reef
C) nectar from floral nectaries.
fishes. What benefit do they provide to those other fish?
D) all of the above
A) They suppress diseases because they consume
E) Both enlarged thorns to host ant colonies and
carcasses of dead fish.
nectar from foliar nectaries.
B) They keep water oxygenated because they
consume organic debris before it can rot.
C) They keep fish relatively free of externally8. Crabs and shrimp associated with corals protect their
feeding parasites.
hosts from
D) They maintain fish habitat by keeping corals free
A) being dislodged from the substrate by currents.
of encrusting algae.
B) predation by sea-stars.
E) They reduce fish mortality by repelling large
C) predation by fishes.
vertebrate predators.
D) attack by parasitic nematodes.
E) infection by pathogenic bacteria.
4. The largest reservoir of phosphorus in most
ecosystems is phosphorus
A) in the atmosphere.
D) bound in animal tissues.
B) dissolved in water. E) bound in plant tissues.
C) in rocks and sediments.
9. Wayne Sousa's studies of succession on intertidal
boulders demonstrated which elements of the inhibition
hypothesis?
A) inhibition of mid- and late-successional species
by pioneers
B) inhibition of late-successional species by midsuccessional ones
C) higher mortality of pioneer species
D) all of the above
E) none of the above
5. Robert MacArthur's study of forest warblers
suggested that
A) fewer warbler species can survive in more
complex habitats.
B) warbler species diversity increases with habitat
complexity.
C) warbler species diversity decreases with habitat
complexity.
D) most warblers have rather similar foraging
niches.
E) none of the above
1
10. According to the ìfacilitationî hypothesis, pioneer
species modify the environment in ways that
A) make it more suitable for their own survival,
and less suitable for other species.
B) make it less suitable for their own survival, but
more suitable for survival of other pioneer
species.
C) make it less suitable for their own survival, but
more suitable for survival of late-successional
species.
D) make it less suitable for survival of all species.
E) make it more suitable for survival of all species.
11. A major perturbation of the carbon cycle by human
activity is associated with
A) release of carbon from carbonate rocks.
B) release of carbon from fossil fuel deposits.
C) removal of carbon from the atmosphere in the
industrial production of fertilizers.
D) accelerated removal of carbon from the
atmosphere by forests.
E) respiratory production of CO2 by the large
human population.
12. Actual evapotranspirationî for an ecosystem refers to
the amount of water that
A) is taken up from soils by plant roots.
B) evaporates from soils.
C) is transpired by plants.
D) evaporates from soils plus the amount
transpired by plants.
E) could evaporate from soils, if they were kept
wet at all times.
Fill in the Blank
13.
Ecologists summarize feeding interactions among species in a community when they compile a
_________.
14.
Primary producers make up the first, or basal, ____________ in most food webs.
15.
A tendency for a community to maintain its structure even when subject to potential disturbance is called
____________.
16.
A mutualistic relationship in which either species can survive without its partner is called a
______________ mutualism.
True/False
17. Streams with higher densities of stream invertebrates would be expected to have shorter spiralling lengths.
A) True
B) False
18. The impact of Argentine ants on species diversity in the South African fynbos is most dramatic following fires
A) True
B) False
19. Among marine systems, primary productivity is highest in tropical portions of the major oceans, far from
terrestrial influences.
A) True
B) False
1.B
2.C
3.C
4.C
5.B
6.E
7.D
8.B
9.D
10.C
11.B
12.D
13.food web
14.trophic level
15.resistance
16.facultative
17.A
18.A
19.B
Page 2