Name: 
 

Ecology Review


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

1. 
The size of a population is controlled by all but which of the following?
a.
biotic potential
b.
feeding level
c.
carrying capacity of the environment
d.
death rate
e.
birth rate
 

2. 
The relationship between the yucca plant and the yucca moth that pollinates it is best described as
a.
camouflage.
b.
commensalism.
c.
competitive exclusion.
d.
obligate mutualism.
e.
all of these
 

3. 
In brown air fog, which substance combines with nitrogen dioxide in the sunlight to form photochemical smog?
a.
carbon monoxide
b.
water vapor
c.
hydrocarbons
d.
sulfuric acid
e.
all of these
 

4. 
The ocean zone that exhibits the greatest degree of species diversity is
a.
estuary.
b.
rocky intertidal.
c.
neritic.
d.
continental shelf.
 

5. 
A biome with grasses as primary producers and scattered trees adapted to prolonged dry spells is known as a
a.
warm desert.
b.
savanna.
c.
tundra.
d.
taiga.
e.
chaparral.
 

6. 
The interaction between two species in which one species benefits and the other species is harmed is
a.
mutualism.
b.
commensalism.
c.
competition.
d.
predation.
e.
none of these
 

7. 
The biotic potential
a.
varies from one species to another.
b.
is controlled by the timing of the first reproduction.
c.
is controlled by the frequency of reproduction.
d.
is controlled by the number of offspring produced.
e.
all of these
 

8. 
Approximately what percentage of the earth's land is not usable, or even potentially usable, for agriculture?
a.
25
b.
50
c.
15
d.
75
e.
0;  all is potentially usable
 

9. 
In a natural community, the primary consumers are
a.
herbivores.
b.
carnivores.
c.
scavengers.
d.
decomposers.
e.
all of these
 

10. 
In contrast to a predator, a parasite usually
a.
does not kill the animal on which or in which it lives.
b.
kills its host.
c.
is a short-term visitor.
d.
is larger than its host.
e.
does not kill the animal on which or in which it lives and is larger than its host.
 

11. 
Populations of most species
a.
are relatively constant over time.
b.
gradually decrease over time.
c.
gradually increase over time.
d.
vary rapidly, depending upon environmental conditions.
 

12. 
Water molecules reside for the longest time in which phase of the hydrologic cycle?
a.
detention
b.
evaporation
c.
precipitation
d.
transportation
 

13. 
Which of the following combinations of organisms could be expected to survive in isolation from other forms of life available?
a.
producers and decomposers
b.
producers and carnivores
c.
carnivores and decomposers
d.
herbivores, carnivores, and decomposers
 

14. 
All but which of the following factors appear to be correlated with a decrease in atmospheric ozone?
a.
suppression of the immune system
b.
decreased rates of photosynthesis
c.
increased incidence of skin cancers
d.
decreased levels of atmospheric carbon dioxide
 

15. 
Most of the carbon now present in the earth's atmosphere will eventually end up in what two "holding stations"?
a.
plants and animals
b.
plants and decomposers
c.
plants and soil
d.
plants and oceans
e.
plants and fossil fuels
 

16. 
Air pollution
a.
reduces visibility.
b.
corrodes buildings.
c.
causes various human diseases.
d.
damages plants.
e.
all of these
 

17. 
The amount of energy that flows through a detrital food web is __________ that which flows through a grazing web.
a.
the same as
b.
greater than
c.
less than
d.
the sum of
e.
the difference of
 

18. 
To be a part of the biosphere, any particular region must
a.
be close to the earth's surface.
b.
include plenty of water.
c.
support life.
d.
include oxygen.
e.
be terrestrial.
 

19. 
The most harmful element in coal that causes serious pollution problems is
a.
nitrogen.
b.
silver.
c.
carbon.
d.
sulfur.
e.
chlorine.
 

20. 
Zero population growth is achieved when
a.
a population reaches the carrying capacity of the environment.
b.
the population size has been stabilized for a long time.
c.
births exceed deaths.
d.
deaths exceed births.
e.
migration is prevented.
 

21. 
Evergreen trees are found in the
a.
tropics.
b.
temperate zones.
c.
taiga.
d.
temperate zones and taiga, only.
e.
tropics, temperate zones, and taiga.
 

22. 
The distribution of the human population in the United States is
a.
clumped.
b.
random.
c.
uniform.
d.
constant.
 

23. 
Of the energy that enters one trophic level, approximately what percent becomes available for the next trophic level?
a.
100
b.
10
c.
1
d.
0.1
e.
0.01
 

24. 
Concerning biomes where maple and beech trees are the dominant vegetation, which of the following statements is true?
a.
Winters are warm.
b.
Rainfall is low.
c.
Rate of evaporation is low.
d.
Soil nutrient concentration is high.
 

25. 
Which of the following is NOT one of the factors that control the dispersion of organisms in nature?
a.
Most environmental resources are randomly distributed.
b.
Biological conditions tend to be patchy.
c.
Dispersal of seeds and young organisms is often limited or controlled by environmental factors.
d.
The development of societies in some populations controls distribution.
e.
Physical features in the environment are not generally uniform.
 

26. 
Which of the following would be expected to have the LEAST effect on the materials suspended in the waters of a stream?
a.
agricultural wastes
b.
microorganisms
c.
vertebrate animals
d.
trees along the banks
e.
rocks and sand in streambed
 

27. 
In natural communities, some feedback mechanisms operate whenever populations change in size; they are
a.
density-dependent factors.
b.
density-independent factors.
c.
always intrinsic to the individuals of the community.
d.
always extrinsic to the individuals of the community.
e.
none of these
 

28. 
Which of the following acids is a severe air pollutant?
a.
carbonic acid
b.
nitric acid
c.
hydrofluoric acid
d.
hydrochloric acid
e.
boric acid
 

29. 
What term denotes the range of all factors that influence whether a species can obtain resources essential for survival and reproduction?
a.
habitat
b.
niche
c.
carrying capacity
d.
ecosystem
e.
community
 

30. 
The biomass of a community is the weight of the
a.
material decomposed in a year.
b.
producers.
c.
living organisms.
d.
consumers.
e.
decomposers.
 

31. 
Of the following, which would probably be the safest source of drinking water?
a.
municipal water supply
b.
clear mountain stream
c.
deep well
d.
shallow well
e.
rainwater
 

32. 
Which of the following statements about nuclear power plants is true?
a.
Their net energy production is relatively low.
b.
Their waste products lead to the production of acid rain.
c.
Their waste products are not radioactive.
d.
Their net energy production is relatively low; and Their waste products lead to the production of acid rain.
e.
Their net energy production is relatively low; Their waste products lead to the production of acid rain; and Their waste products are not radioactive.
 

33. 
A process in which nitrogenous waste products or organic remains of organisms are decomposed by soil bacteria and fungi that use the amino acids being released for their own growth and release the excess as NH3 or NH4+ is
a.
nitrification.
b.
ammonification.
c.
denitrification.
d.
nitrogen fixation.
e.
hydrogenation.
 

34. 
Which concept is a way to express the growth rate of a given population?
a.
doubling time
b.
population density
c.
population size
d.
carrying capacity
e.
all of these
 

35. 
Grassland biomes around the earth vary in several ways, but the chief factor causing the variation is
a.
rainfall amounts.
b.
vegetation.
c.
soil type.
d.
the animals present.
e.
prevailing winds.
 

36. 
Biological magnification refers to the
a.
increase in size of animals as they progress through a food chain.
b.
increase in size of organisms as they progress through ecological succession.
c.
increase in the efficiency of energy utilization as organisms progress through a food chain.
d.
accumulation of toxic pollutants as animals pass through a food chain.
 

37. 
Upwelling
a.
increases productivity by bringing nutrient-rich cool water to the surface of the ocean.
b.
occurs in freshwater lakes when the thermocline is destroyed by changing temperatures.
c.
refers to the accumulation of pollution in certain estuaries.
d.
occurs when warm ocean currents approach the edge of continents.
e.
generates the major climatic changes in the Pacific Ocean known as El Niño.
 

38. 
What is the main drawback to the use of wind energy?
a.
It is too costly.
b.
Winds don't blow on a regular schedule.
c.
The technology is not yet available.
d.
Windmills are unsightly.
e.
The energy is not as good as that produced by other means.
 

39. 
Which of the following is NOT a factor that has led to the dramatic increase in the human population?
a.
increase of carrying capacity
b.
removal of several limiting factors
c.
human invasion of new habitats and climatic zones
d.
an increase in the levels of pollution in the world
e.
the development of public health and the germ theory of disease
 

40. 
The interaction between two species in which both species may be harmed is known as
a.
mutualism.
b.
parasitism.
c.
commensalism.
d.
competition.
e.
predation.
 

41. 
Detritivores are
a.
bacteria.
b.
plants.
c.
fungi.
d.
animals.
e.
both bacteria and fungi.
 

42. 
Which of the following factors is most important in determining the type of biomes found in a particular region?
a.
soil type
b.
light intensity
c.
temperature
d.
type of animals in the region
 

43. 
The atmosphere above which region is known to have a hole in the ozone layer?
a.
Antarctica
b.
eastern North America
c.
northern Europe
d.
the western Pacific
 

44. 
The carrying capacity of an environment is determined by
a.
the net rate of reproduction of the female members.
b.
an S-shaped curve.
c.
the predation rate on the females.
d.
diseases suffered by both sexes.
e.
the sustainable supply of resources it provides.
 



 
Check Your Work     Reset Help