Name: 
 

Unit 8: Ecology


Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
 

 1. 
Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?
a.
community, ecosystem, individual, population
b.
ecosystem, community, population, individual
c.
population, ecosystem, individual, community
d.
individual, population, community, ecosystem
e.
individual, community, population, ecosystem
 

 2. 
Which of the following abiotic factors has the greatest influence on the metabolic rates of plants and animals?
a.
water
b.
wind
c.
temperature
d.
rocks and soil
e.
disturbances
 

 3. 
The success with which plants extend their range northward following glacial retreat is best determined by
a.
whether there is simultaneous migration of herbivores.
b.
their tolerance to shade.
c.
their seed dispersal rate.
d.
their size.
e.
their growth rate.
 

 4. 
You are planning a dive in a lake, and are eager to watch underwater organisms both close up and far away. You would do well to choose
a.
a nutrient-poor lake.
b.
a nutrient-rich lake.
c.
a relatively deep lake.
d.
A and C only
e.
B and C only
 

 5. 
An area in which different terrestrial biomes grade into each other is known as a(n)
a.
littoral zone.
b.
vertically stratified canopy.
c.
ecotone.
d.
abyssal zone.
e.
cline.
 

 6. 
Which of the following is a behavioral pattern resulting from an ultimate cause?
a.
A male robin attacks a red tennis ball because it resembles the breast of another male.
b.
A male robin attacks a red tennis ball because it is spring and hormonal changes increase its aggression.
c.
A male robin attacks a red tennis ball because a part of its brain is stimulated by objects that are red.
d.
A male robin attacks a red tennis ball because several times in the past red tennis balls have been thrown at it, and it has learned that they are dangerous.
e.
A male robin attacks a red tennis ball because it confuses it with an encroaching male who will steal his territory.
 
 
Below is a list of signal types that animals use for communication. Choose the one that best fits the criteria in the following questions.

A)
olfactory
B)
visual
C)
auditory
D)
tactile
E)
electrical
 

 7. 
A fast signal that requires daylight and no obstructions.
a.
A
b.
B
c.
C
d.
D
e.
E
 

 8. 
The type of learning that causes specially trained dogs to salivate when they hear bells is called
a.
insight.
b.
imprinting.
c.
habituation.
d.
classical conditioning.
e.
trial-and-error learning.
 

 9. 
Stevan Arnold discovered that coastal and inland garter snakes reacted differently to banana slug prey. What probably accounts for such a difference?
a.
Ancestors of coastal snakes that were able to eat the abundant slugs had increased fitness. No such selection occurred inland, where slugs were absent.
b.
Slugs are difficult to see, and inland snakes, which have poor vision compared with coastal snakes, are less able to see them.
c.
Garter snakes learn about prey from other garter snakes. Inland snakes are less social, and this lowers prey diversity.
d.
Inland snakes overlap with distasteful slugs, and thus learn to avoid them. Coastal slugs are not distasteful.
e.
Garter snakes are conditioned to eat what their mother eats. The mothers of Arnold's coastal snakes happened to prefer slugs.
 

 10. 
The evolution of mating systems is most likely affected by
a.
population size.
b.
care required by young.
c.
certainty of paternity.
d.
B and C only
e.
A, B , and C
 

 11. 
In Belding's ground squirrels, it is mostly the females that behave altruistically by sounding alarm calls. What is the likely reason for this distinction?
a.
Males have smaller vocal cords and are less likely to make sounds.
b.
Females invest more in foraging and food stores, so they are more defensive.
c.
Females settle in the area in which they were born, so the calling females are warning kin.
d.
The sex ratio is biased.
e.
Males forage alone; therefore, alarm calls are useless.
 

 12. 
You are studying the mice that live in a pasture near your home. There are lots of mice in this pasture, but you realize that you rarely observe any reproductive females. This most likely indicates
a.
that there is selective predation on female mice.
b.
that female mice die before reproducing.
c.
that this habitat is not a good place for mice to reproduce.
d.
that you are observing immigrant mice.
e.
both C and D
 

 13. 
Natural selection involves energetic trade-offs between or among life history traits such as
a.
number of offspring per reproductive episode.
b.
number of reproductive episodes per lifetime.
c.
age at first reproduction.
d.
A and C only
e.
A, B, and C
 
 
Use the following choices to answer the question below. Each choice may be used once, more than once,or not at all.

A.
unit8_ecology_files/i0160000.jpg
B.
unit8_ecology_files/i0160001.jpg
C.
unit8_ecology_files/i0160002.jpg
D.
unit8_ecology_files/i0160003.jpg
E.
unit8_ecology_files/i0160004.jpg
 

 14. 
Exponential growth of a population is represented by dN/dt =
a.
A
b.
B
c.
C
d.
D
e.
E
 

 15. 
Which of the following might be expected in the logistic model of population growth?
a.
As N approaches K, b increases.
b.
As N approaches K, r increases.
c.
As N approaches K, d increases.
d.
Both A and B are true.
e.
Both B and C are true.
 

 16. 
In a mature forest of oak, maple, and hickory trees, a disease causes a reduction in the number of acorns produced by oak trees. Which of the following would least likely be a direct result of this?
a.
There might be fewer squirrels because they feed on acorns.
b.
There might be fewer mice and seed-eating birds because squirrels would eat more seeds and compete with the mice and birds.
c.
There might be an increase in the number of hickory trees because the competition between hickory nuts and acorns for germination sites would be reduced or eliminated.
d.
There might be fewer owls because they feed on baby squirrels, mice, and young seed-eating birds, whose populations would be reduced.
e.
There might be a decrease in the number of maple seeds as the disease spreads to other trees in the forest.
 

 17. 
All of the following have contributed to the growth of the human population except
a.
environmental degradation.
b.
improved nutrition.
c.
vaccines.
d.
pesticides.
e.
improved sanitation.
 

 18. 
The entire box shown in the figure below represents the niche of species A. Species A is biologically constrained from the striped area of its niche by species B. This is an example of

unit8_ecology_files/i0210000.jpg
a.
dynamic stability.
b.
facilitation.
c.
commensalism.
d.
competitive exclusion.
e.
secondary succession.
 

 19. 
Which of the following types of species interaction is incorrectly paired to its effects on the density of the two interacting populations?
a.
predation-one increases, one decreases
b.
parasitism-one increases, one decreases
c.
commensalism-both increase
d.
mutualism-both increase
e.
competition-both decrease
 

 20. 
Consider a field plot containing 200 kg of plant material. Approximately how many kg of carnivore production can be supported?
a.
200
b.
100
c.
20
d.
10
e.
2
 

 21. 
In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field. A possible factor in this secondary succession was
a.
equilibrium.
b.
facilitation.
c.
immigration.
d.
inhibition.
e.
mutualism.
 
 
Refer to the diagram below of five islands formed at about the same time near a particular mainland to answer the following questions.

unit8_ecology_files/i0250000.jpg
 

 22. 
island with the lowest extinction rate
a.
A
b.
B
c.
C
d.
D
e.
E
 

 23. 
A biologist measures predation rates by crab spiders on flower-visiting insects in a particular field community. Then the biologist experimentally removes as many of the spiders as she can. She discovers that predation rates remain the same but that the major predators shift from spiders to ambush bugs. Which of the following community structure models is most consistent with her findings?
a.
individualistic
b.
integrated
c.
rivet
d.
redundancy
e.
manipulative
 

 24. 
Production, consumption, and decomposition are important ecosystem processes. Which of the following could be decomposers?
a.
bacteria
b.
vertebrates
c.
invertebrates
d.
A and C only
e.
A, B, and C
 

 25. 
Which of these ecosystems has the highest net primary productivity per square meter?
a.
savanna
b.
open ocean
c.
boreal forest
d.
tropical rain forest
e.
temperate forest
 

 26. 
Some aquatic ecosystems can have inverted biomass pyramids because
a.
phytoplankton are much larger than zooplankton.
b.
phytoplankton have a relatively short life cycle.
c.
consumption of phytoplankton by zooplankton is so rapid that the standing crop of phytoplankton remains relatively low.
d.
B and C only
e.
A, B, and C
 

 27. 
If you were tracking a nutrient molecule through an ecosystem, which of the following statements would you expect to verify?
a.
Molecules move through all ecosystems at the same constant rate, as the laws of physics would predict.
b.
Because of the liquid nature of the aquatic ecosystem, nutrient molecules move through it rapidly compared with forest ecosystems.
c.
Vertical mixing is essential for high productivity in aquatic ecosystems.
d.
A and B only
e.
A, B, and C
 

 28. 
The high levels of pesticides found in birds of prey is an example of
a.
eutrophication.
b.
predation.
c.
biological magnification.
d.
the green world hypothesis.
e.
chemical cycling through an ecosystem.
 

 29. 
According to the U.S. Endangered Species Act (ESA), the difference between an endangered species and a threatened one is that
a.
an endangered species is closer to extinction.
b.
a threatened species is closer to extinction.
c.
threatened species are endangered species outside the U.S. borders.
d.
endangered species are mainly tropical.
e.
There is no real difference.
 

 30. 
If the sex ratio in a population is significantly different from 50:50, then which of the following will always be true?
a.
The population will enter the extinction vortex.
b.
The genetic variation in the population will increase over time.
c.
The genetic variation in the population will decrease over time.
d.
The effective population size is greater than the actual population size.
e.
The effective population size is less than the actual population size.
 

 31. 
Wildlife movement corridors can
a.
promote gene flow.
b.
promote disease transmission.
c.
assist migratory species.
d.
A and C only
e.
A, B, and C
 

 32. 
Human use of prokaryotic organisms to help detoxify a polluted wetland would be an example of
a.
ecosystem augmentation.
b.
keystone species introduction.
c.
biological control.
d.
bioremediation.
e.
population viability analysis.
 

 33. 
Which of the following is (are) related to the agenda of the Sustainable Biosphere Initiative?
a.
defining what ecological studies are needed for conserving Earth's resources
b.
maintaining productivity of human-made as well as natural ecosystems
c.
understanding interactions between climate and ecological dynamics
d.
resource management and development
e.
all of the above
 



 
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