Name__________________
Practice Exam
APES
Unit 3: Ecology & The Living World
1. Interspecific competition differs from intraspecific competition in
that:
7. A keystone species
(1)
(2)
(3)
(4)
(5)
(1) interspecific involves competition between different species, while
intraspecific involves competition within one species.
(2) interspecific involves competition within one species, while
intraspecific involves competition between different species.
(3) interspecific occurs when indirect effects decrease resources,
while intraspecific occurs when direct effects increase
resources.
(4) interspecific occurs when direct effects decrease resources,
while intraspecific occurs when indirect effects increase
resources.
(5) None of the above are accurate.
(1)
(2)
(3)
(4)
(5)
(3) II, III
(4) II, I
consume competing native species
displace competing native species
disrupt the water cycle
increase carbon dioxide intake
reduce land fertility
9. The theory that one of two species sharing the same niche will be
eliminated by the more efficient species is called
(1) competitive exclusion
(2) K-strategy
(3) niche specificity
I. clam attached to the gills of a fish, absorbing
nutrients from the fish
II. lions prey upon zebras for food
III. two species of honeybees competing for the
same hive
(2) I, III
all of the above
8. When introduced into an ecosystem, invasive plant species
2. Parasitism and predation both involve a benefit to one organism with
a cost to the other organism. Which of the following is an example of
parasitism and predation, respectively? (1) I, II
can be a limiting factor
is important in maintaining biological diversity
affects other species in the ecosystem
affects the available food and other resources in the ecosystem
(4) stabilizing selection
(5) total extinction
10. Over time, most populations exhibit a sigmoid growth curve that
levels off at a value K. This value is known as
(1)
(2)
(3)
(4)
(5)
(5) III, II
3. Which of the following adaptation is paired with the correct
environment?
(1) In the tropics, plants possess leaves with small surface area to
avoid increased transpiration.
(2) In temperate forests, deciduous trees drop leaves, which is an
energy expense.
(3) Drought-resistant grass species have developed in grasslands and
carrying capacity
equilibrium growth rate
exponential growth rate
logistic growth rate
minimum population density
11.
prairies.
(4) Insects in deserts have thin protective coverings, which
regulates body temperature.
(5) In tundra, plants continuously grow to increase survival.
4. If a species of finches is selectively bred for narrower beaks,
(1) genes for broader beaks will become more abundant in the
breeding population
(2) genes for narrower beaks will become more abundant and genes
Based on the graph above, which curve represents the survivorship
curve for elephants and why?
for broader beaks will become less abundant in the breeding
population
(3) genes for broader beaks will be lost completely
(4) mutations for narrower beaks will be eliminated
(5) no change will occur due to the nature of the genome
(1) A, because elephants produce few young and care for them until
they reach reproductive maturity.
(2) C, because elephants produce few young and care for them
until they reach reproductive maturity.
(3) B, because elephants have a uniform death rate.
(4) C, because elephants have high juvenile mortality.
(5) A, because elephants have high juvenile mortality.
5. Most pests are
(1) K-selected organisms
(2) equilibrial populations
(3) long-lived
(4) r-strategists
(5) none of the above
6. The role of an organism in the ecosystem is its
(1) community
(2) niche
(3) habitat
12. Which of the following types of species would be least susceptible
to the fragmentation of its habitat due to human influences?
(4) microcosm
(5) ecotone
(1) Generalists
(2) Specialists
(3) Large predators
Page 1
(4) Migratory species
(5) K-selected species
Name__________________
Practice Exam
APES
Unit 3: Ecology & The Living World
13. Base your answer to the following question on the diagram below of 16. Base your answer to the following question on the diagram below.
a particular population that changes with time when subjected to
A pair of antelope, A, lives on 1 square mile of land. A second pair,
limited resources and various external stresses.
B, lives on 4 square miles of land, in which 0.25 of the 4 square
miles overlaps the territory of the first pair.
Both pairs A and B are members of the same species. Which of the
following explains why area B is larger than area A?
Which lettered portion most likely corresponds to when the
reproductive time lag, or the period needed for the birth rate to fall
and the death rate to rise in response to resource over consumption?
(1) A
(2) B
(3) C
(4) D
(1)
(2)
(3)
(4)
(5)
Pair B is bigger
Pair B has less food in its area
Pair A has fewer offspring
Pair B has more available resources
Pair A is more defensive
17. The earth can support more people if they eat
(5) E
(1)
(2)
(3)
(4)
(5)
14. Base your answer to the following question on the following
predator-prey diagram.
only tertiary carnivores
higher trophic levels
constant trophic levels
lower trophic levels
only secondary carnivores
18.
Which of the following is a valid conclusion that can be made from
the above diagram? I. A carrying capacity is limiting the growth of the prey,
causing prey population to crash. II. The predator is controlling the prey population and reduces
the prey population periodically. III. A decline in the prey population will lead to a decline in the
predator population.
(1) I only
(2) II only
(3) III only
(4) I and III only
(5) II and III only
Which of the following organisms is likely to be the keystone
species?
15. When the niches of two species overlaps significantly, which of the
following is NOT likely to happen?
(1)
(2)
(3)
(4)
(5)
One of the species migrates.
The niche evolves to accommodate both species.
One of the species evolves.
One of the species suffers a decline in population.
One of the species becomes extinct.
(4) Krill
(5) Benthos mudworms
(1) Bacteria
(2) Squids
(3) Whales
19. Which of the following organisms occupies the lowest trophic
level?
(1) Spider
Page 2
(2) Moose
(3) Tiger
(4) Eagle
(5) Snake
Name__________________
Practice Exam
APES
Unit 3: Ecology & The Living World
20. Which of the following statements concerning biodiversity and
ecosystem stability is FALSE?
28. Which of the following animals occupies the highest trophic level?
29. The biome that contains the most biodiversity is
(1) a desert
(2) a temperate forest
(3) a tropical rain forest
ecosystem, the more stable that ecosystem is.
(4) Ecosystems with higher biodiversity tend to have lower net
productivities.
(5) Ecosystems with higher biodiversity tend to fluctuate less
widely than simpler ones.
(4) a tropical savannah
(5) a taiga
30. Herbivores are often considered to be what type of organisms in a
typical food chain?
(1) Producers
(2) Primary consumers
(3) Secondary consumers
21. Which of the following is a starting point for primary succession?
(1)
(2)
(3)
(4)
(5)
(4) Hawk
(5) Dragonfly
(1) Snake
(2) Squirrel
(3) Deer
(1) The more diverse an ecosystem is, the less redundancy there
is with species occupying the same niches.
(2) There is a minimum threshold of species diversity below
which ecosystems cannot work.
(3) Without exception, the higher the species diversity of an
Abandoned farmland
Flooded land
Polluted streams
Burned down pine barrens
(4) Carnivores
(5) Decomposers
31.
An abandoned parking lot
22. If the ecological efficiency of a particular ecosystem is 10% and the
plants in this ecosystem capture 10,000 units of energy, how many
units of energy will be available to support the primary consumers?
(1) 100,000 (2) 10,000
(3) 1,000
(4) 100
(5) 10
23. The majority of the energy put into the food chain
(1)
(2)
(3)
(4)
(5)
In the food web above, which animals are tertiary consumers?
is in the form of heat
is converted to biomass by the end of the chain
is recycled by the end of the chain
(1) Rabbits and sparrows
(2) Sparrows and hawks
(3) Snakes and hawks
exits in the form of low quality waste heat
32. In a food pyramid, the organisms in the trophic level associated
with the greatest amount of energy are
is used efficiently by the end of the chain
24. Each of the following are consumers EXCEPT
(1)
(2)
(3)
(4)
(5)
(4) autotrophs
(5) herbivores
(1) decomposers
(2) omnivores
(3) carnivores
25. Base your answer to the following question on the following
processes.
(3) C
(4) D
(5) E
26. The first trophic level in an ecosystem includes
(1) carnivores
(2) consumers
(3) secondary consumers
(2) 30%
(3) 50%
(4) 70%
(4) Wolves
(5) Rabbits
34. An African plant evolves to have small needle-like leaves and a
waxy surface because of the hot and dry climate. A plant in
Arizona from a completely different ancestor evolves in a similar
fashion because of a similar climate. What is this an example of?
(1) Stabilizing selection
(2) Speciation
(3) Divergent evolution
(4) herbivores
(5) autotrophs
27. What percentage of energy is generally said to be lost as one moves
from one level to the next on the biomass-energy pyramid?
(1) 10%
the primary consumers
the secondary consumers
the tertiary consumers
the decomposers
(1) Mushrooms
(2) Caterpillars
(3) Oak trees
The process that supplies most of the dissolved oxygen in oceans
(2) B
the producers
33. In a forest food chain, the least amount of energy would flow to
which of the following organisms?
(A) Decomposition
(B) Assimilation
(C) Denitrification (D) Transpiration
(E) Photosynthesis
(1) A
(4) Frogs and foxes
(5) Mice and grasshoppers
(4) Convergent evolution
(5) Comparative anatomy
35. What percent of all species that ever existed do biologists
estimate are now extinct?
(1) 5%
(5) 90%
Page 3
(2) 25%
(3) 50%
(4) 75%
(5) 99%
Name__________________
Practice Exam
APES
Unit 3: Ecology & The Living World
36. Base your answer to the following question on the drawing below of
the pyramid of energy and numbers.
40. Which of the following is a FALSE assertion made by the modern
theory of evolution?
I. Natural selection favors population of species that win in
direct competition over niches.
II. Humans evolved from apes.
III. Species are progressively becoming more and more perfect.
(1) I only
(2) II only
(3) III only
(4) II and III only
(5) I, II, and III
41. For natural selection to occur, which of the following conditions in
a population is necessary?
(1) Reproduction must be relatively similar for all members of the
population.
(2) The ecosystem in which the population resides must be stable.
(3) Mating must be random.
(4) The trait must be heritable.
(5) The population must be isolated from all other populations.
In which level would a monarch caterpillar that feeds on the
milkweed plant belong to?
(1) 1
(2) 2
(3) 3
(4) 4
(5) none of the above
37. A group of students studying the ecology of a freshwater stream
recorded data in the following categories:
42. Pollution from a nearby city has caused all the trees in a forest to
change from dark brown to white. The dark brown moths that used
color as camouflage suffer increased predation. A mutation
produces white moths which increase in population. What is this an
example of?
(A) kinds of insects
(B) pH
(C) number of minnows
(D) mineral concentration
(E) types of producers
(F) oxygen content
(G) examples of food chains
(H) water temperature
(1) Mutation
(2) Natural selection
(3) Selective pressure
Which group of data categories contains only biotic factors of the
stream?
(1) A, B, C, and D
(2) B, C, E, and G
(3) A, C, G, and H
(1)
(2)
(3)
(4)
(5)
43. What type of evolutionary process is especially important for small
populations and involves change of the genetic composition of a
population by chance?
(1) Genetic drift
(2) Gene flow
(3) Speciation
(4) C, E, F, and G
(5) A, C, E, and G
38. A certain type of herbivore favors a certain type of flower. The
flower evolves to grow thorns and thus evades predation for a
while. However the herbivore evolves to have a longer snout in
order to get around the thorns. What is this an example of?
(4) Natural selection
(5) Mutation
44. Which of the following types of mutation can cause evolution?
(1) Mutagenic chemical compounds causing stomach cells to
mutate.
(2) X ray radiation causing mutation in mouth tissue.
(3) Random mistakes when DNA is copied in brain cells.
(4) UV radiation exposure of skin cells, leading to mutation.
(5) Random mistakes when DNA is copied in reproductive cells.
Predation
Predator-prey relationship
Coevolution
Diversifying natural selection
Gene flow
(4) Genetic drift
(5) Competition
45. Which of the following does NOT explain why Darwin’s finches on
the Galapagos Islands experience speciation?
39. Which of the following best illustrates the process of evolution?
(1) The birds on each island evolved their own genetic pool.
(2) Mutations led to the development of new species.
(3) They experienced different selective pressures on each of the
islands.
(4) Genetic drift led to adaptive radiation.
(5) Isolation from birds on other islands led to speciation.
(1) A culture of bacteria develops resistance against a specific
antibiotic.
(2) A species of rabbits increase as the predator population
decreases.
(3) A bear hibernates.
(4) A frog's skin color changes to blend into new surroundings.
(5) A plant sheds its leaves to prepare for winter.
Page 4
Name__________________
Practice Exam
APES
Unit 3: Ecology & The Living World
46. Which of the following is FALSE regarding natural selection?
(1) Natural selection occurs at the level of individual organisms,
not populations.
(2) Natural selection occurs over successive generations.
(3) Natural selection is caused by evolution.
(4) Natural selection will not occur unless the environment
changes.
(5) Natural selection can be stabilizing.
53. Over time, plants and animals have adapted their reproductive
strategies to maximize their survival. Two examples include
R-strategists and K-strategists.
a. List 8 differences between the reproductive characteristics of
R-strategists and K-strategists.
b. Which type of strategists are more prone to extinction? Why?
47. All of the following increase biological diversity EXCEPT
(1)
(2)
(3)
(4)
(5)
natural disturbances
evolution
low variation in temperature, rainfall
geographic isolation
middle stages of succession
48. Some organisms are better able to pass on their genes to their
offspring when compared to other organisms. This is known as
(1) adaptation
(2) gene flow
(3) genetic drift
(4) natural selection
(5) differential reproduction
49. Which of the following is NOT an example of how nitrogen is
"fixed" and made ready for plant consumption?
(1) Bacteria in aquatic and terrestrial systems convert N into
compounds such as NH24+
(2) Fungi convert nitrogenous wastes in soil into nitrogen
containing nutrients.
(3) Humans take nitrogen and put it in fertilizers such as NH4NO3
which is sold commercially. (4) Atmospheric discharge in the form of lightning can convert N
into compounds like NO2.
(5) N2 is taken directly by plants from the atmosphere and converted
to compounds such as NH3.
50. The process in which Rhizobium bacteria in the root systems of
legumes converts nitrogen into ammonia is
(1) assimilation
(2) ammonification
(3) nitrification
(4) denitrification
(5) nitrogen fixation
Base your answers to questions 51 and 52 on the components of the
nitrogen cycle listed below.
(A) Nitrifying bacteria
(B) Denitrifying bacteria
(C) Decomposing bacteria
(D) Nitrogen-fixing bacteria
(E) Aerobic fungi
51. Which organisms convert ammonium (NH4+) into nitrites (NO2–)?
52. Which organisms convert nitrogen (N2) and hydrogen (H2) into
ammonia (NH3)
Page 5
Name__________________
APES
Practice Exam
Unit 3: Ecology & The Living World
54. Phytoplankton are microscopic plants that live in oceanic waters. Many organisms feed on phytoplankton, including Pelagic
decapods, Pelagic mysids, and Artic cod. Artic cod also eat Pelagic decapods and Pelagic mysids, and in turn serve as the food
source for harp seals, as well as people. The pesticide DDT, dichlorodiphenyl trichloroethane, was banned in the United States in
1973. However, DDT has been detected in most test site water. DDT has been found in fish, such as artic cod.
a) In the space below, diagram a food web based on the interactions of all of the organisms described in the
above passage. Be sure to include tropic levels and identification or producers and consumers. b) Describe the past use of DDT and discuss the impact of DDT on the food supply and on humans.
c) Discuss a strategy of integrated pest management to protect crops, as an alternative to pesticides.
Discuss a strategy of integrated pest management to protect crops, as an alternative to pesticides.
Page 6
Answer Key
Test 3 Ecology
1.
1
42.
2
2.
1
43.
1
3.
3
44.
5
4.
2
45.
2
5.
4
46.
3
6.
2
47.
4
7.
5
48.
4
8.
2
49.
5
9.
1
50.
5
10.
1
51.
B
11.
1
52.
D
12.
1
53.
13.
3
14.
3
15.
2
16.
2
17.
4
18.
4
19.
2
20.
3
21.
5
22.
3
23.
4
24.
4
25.
5
26.
5
27.
5
a. R-strategists:
1. Have many
offspring.
2. Small body size.
3. Mature rapidly.
4. Little or no
parental
care/protection of
offspring.
5. Adapted to
unstable conditions.
6. Population size
fluctuates widely
above and below
carrying capacity.
7. Most offspring
die before they are
able to reproduce.
8. Have a
28.
4
54.
29.
3
(essay)
30.
2
31.
3
32.
1
33.
4
34.
4
35.
5
36.
2
37.
5
38.
3
39.
1
40.
5
41.
4
Page 7
Answer Key
Test 3 Ecology
54.
Answers should include at least the following information:
a) Drawing should include the producer phytoplankton (1st tropic level), eaten by the primary consumers
Pelagic decapods, Pelagic mysids and Artic cod (2nd tropic level). The secondary consumers, Artic cod, eat
Pelagic decapods and Pelagic mysids (3rd tropic level). The tertiary consumers humans and Harp seals consume
the secondary consumers (4th tropic level). Correct arrows and labels are necessary for full credit.
b) DDT was used as an insecticide, especially during World War II. It was used to combat mosquitoes, which
carried malaria and typhus. However, in 1973 it was banned because it was discovered to be a carcinogen, or
cancer-causing agent. DDT enters the food chain directly, and affects all levels. Humans are impacted by eating
fish containing the chemical. Integrated pest management strategies include intercropping, pheromones,
genetically engineered crops with insect-resistance, natural predators, adding mulch.