1. In the diagram to the right, which processes are most closely associated with
the arrows labeled A?
a. runoff and respiration
b. photosynthesis and respiration
c. respiration and transpiration
d. nitrogen fixation and synthesis
2. The abiotic reservoir for the phosphorus cycle is the
a. atmosphere
b. oceans
3. The nitrogen cycle is carried out primarily by
a. humans.
b. termites.
c. rocks
c. bacteria.
d. plants
d. the water cycle.
Use the following to answer questions 37 and 38.
In the laboratory setup shown below, clover plants containing nitrogen-fixing bacteria are cultured under
a glass dome and receive air through an opening in the top. The air used contains nitrogen-15 in place of
normal nitrogen. After two weeks, a grasshopper is allowed to feed on the clover plants.
4. Compounds containing nitrogen-15 pass from bacterial cells
in root nodules to clover plant cells. These compound are
known as
a. amino
b. nitrogen molecules
c. protein
d. nitrates
a.
b.
c.
d.
5. When the grasshopper dies, its tissues will be decomposed.
An immediate effect of this decay on the
surrounding environment would be that
nitrogen is available for further recycling by soil microorganisms
less nitrogen is available than before the grasshopper’s death
ammonia is taken in by nitrogen-fixing bacteria
animal protein is absorbed by clover plants
6. What biogeochemical cycle is represented by the diagram to
the right ?
a. carbon cycle
b. water cycle
c. nitrogen cycle
d. phosphorus cycle
7. Which statement is BEST supported by the diagram of the carbon-oxygen cycle?
a. Combustion adds O2 to the atmosphere and removes CO2
b. Decomposers add O2 to the atmosphere and remove CO2
c. Producers generate O2 and utilize CO2
d. Consumers generate O2 and utilize CO2
1. What is the best way to represent the relationships among organisms in an
ecosystem?
A
As a tree with roots representing decomposers, the trunk representing producers,
and branches representing consumers.
B
A web of interconnecting lines and arrows showing the dependence and
interdependence of living organisms.
C
As a straight line food chain from non-living organisms through producers to
consumers.
D
An arc with arrows pointing from producers to consumers to decomposers.
2. Increased competition with sparrows and starlings for food and nesting sites are
thought to be the cause of the Eastern bluebird’s population decline. Which most likely
caused this increase in competition?
A
shorter growing seasons
B
the addition of birdhouses
C
changing weather patterns
D
the removal of suitable habitats
3. Rabbits are herbivores that are not native to Australia. Their numbers have increased
steadily since being introduced into Australia by European settlers. One likely reason
the rabbit population was able to grow so large is that the rabbits
A
were able to prey on native herbivores
B
could interbreed with the native animals
C
reproduced more slowly than the native animals
D
successfully competed with native herbivores for food
4. A biology student performed an experiment to determine which of two species of
single-celled organisms would survive best when cultured together in a certain
environment. The student placed 10 organisms of each species into a large test tube.
Throughout the experiment, the test tube was maintained at 30°C. After the test tube
was set up, the population of each species was determined each day for 5 days. The
data collected are shown in the table below.
Day
1
2
3
4
5
Population
Species A
Species B
10
10
16
16
32
32
48
12
60
4
The difference in the population sizes on the fifth day most likely resulted from
A
temperature changes.
B
variations in light intensity.
C
the buildup of nitrogen gas.
D
competition between species.
8. In which of the following cases is the size of a population limited by factors within the
organisms environment?
A
More predators move into an area as the number of mice in the area increases.
B
Young pine seedlings have difficulty growing in the shade cast by the canopy of
the mature pines.
C
Each female squirrel in a population has fewer young following a winter of
intense competition for food.
D
A late spring windstorm destroys many nests containing the eggs or new
hatchlings of a bird species.
9. A simple food chain in a wetland is represented below.
algaeparameciummosquito larvatroutblue heron
An ecologist doing population counts in the wetland observes a drop in the number of
trout over an extended period of time. What change is most likely responsible for the
trout decline?
A
migration of blue herons out of the wetland area
B
introduction of a predator that feeds on blue heron eggs
C
application of insecticides to wet areas where mosquitoes breed
D
implementation of new conservation laws to protect the wetland
10. In a pond, the primary producer is a green alga, Spirogyra; the primary consumer is
the crustacean, Daphnia; the secondary consumer is a small fish, the bluegill; and the
tertiary consumer is a larger fish, the smallmouth bass. What changes can be expected
in the pond if the Daphnia are killed with pesticides?
A
The smallmouth bass population will die.
B
The Spirogyra population will probably die.
C
The bluegill population will probably increase.
D
The Daphnia population will eat something else.
11. Many people who raise chickens and other small farm animals consider coyotes to
be pests. These people have decreased the coyote population in many parts of the
United States.
Which of these is likely a result of the decrease in the number of coyotes in the area?
A
The mouse population has increased.
B
The hawk population has decreased.
C
The grass population has increased.
D
The goat population has decreased
12. Which change would increase competition for food among the squirrel population in
a certain area?
A
an increase in the number of squirrels killed on the highways
B
an increase in the number of hawks that prey on squirrels
C
a temporary increase in the squirrel reproduction rate
D
an outbreak of rabies among squirrels
13. A food chain is shown below.
For the food chain shown, which of the following changes would have the most severe
consequences?
A
a drastic decrease in rainfall, causing drought
B
the poaching of predatory hawks by game hunters
C
the introduction of a second predator that eats field mice
D
a parasitic infestation that reduces the cricket population
14. The diet of white-tailed deer consists primarily of shrubs. Sika are another species
of deer that eat both grasses and shrubs. After an extended drought period, why might
the sika population be favored over the white-tailed deer population?
A
Sika require less food than do the white-tailed deer.
B
Sika require more food than do the white-tailed deer.
C
Sika have more food sources than do the white-tailed deer.
D
Sika have fewer food sources than do the white-tailed deer.
01283
15. There is a limit to how large any given population can grow. Which of the following
statements best explains why a population must eventually stop growing?
A
A low female-to-male ratio develops in the population as it grows.
B
Old individuals outnumber juveniles in the population as it grows.
C
The resources available are fully used by the population as it grows.
D
Natural selection changes the gene pool of the population as it grows.
16. In the longstanding war between coyotes and sheep ranchers in New Mexico,
studies show that coyotes kill sheep and the percentage of sheep lost from herds in
areas where coyotes have been exterminated is about the same as the percentage lost
in areas where coyotes are still present.
What is the most likely explanation for the similarity in the percentage of sheep lost in
both areas?
A
Coyotes were protecting sheep.
B
The sheep died from overcrowding.
C
Another predator was killing sheep.
D
Coyotes were preying on sick or weak sheep
17. Use the data to answer question.
Number of Paramecia in Pond Water Sample
Day
Species S
Species T
1
50
50
2
60
80
3
100
90
4
150
60
5
160
50
6
160
30
7
160
20
Which of the following can be correctly concluded from the data?
A
Species S is the food for species T.
B
Species T is more common than species S.
C
Species S is a more successful competitor than species T.
D
Species T is a more successful competitor than species S.
18. Before it was banned, the insecticide DDT was used to combat an organism called
the red mite. An unexpected result of the use of DDT was that population of the red mite
increased rather then decreased, while the population of insect predators of the red mite
decreased. What can be inferred from this scenario?
A
The red mites are immune to the effects of all insecticides.
B
Using insecticides is a reliable way to eliminate all insect predators.
C
The red mite and its insect predators were competing for the same resources.
D
Environmental changes that affect one population may not affect another
population.
19. Study the food web below.
If a new predator of the cricket were introduced into the environment what would most
likely be the affect on the food web?
A
The grass population would decrease.
B
The frog population would decrease.
C
The mountain lion population would increase.
D
The cricket population would increase.
20. The prairie ecosystem shown below suffered a major drought during the summer of
2002.
The Indian grass was the only plant to survive the drastic climate change. What would
be the most likely effect on the primary consumers?
A
The prairie dog population will find new food sources.
B
The locusts will mutate and begin to eat the Indian grass.
C
The quail population will thrive due to a decrease in competition.
D
The quail population will increase due to a decrease in food availability.
Use the passage to answer the next 5 questions.
Scientists are interested in understanding what determines the species richness
(number of different species) of plant communities (al the plants living within a given
area). Scientist agree that the resources necessary for all plants to survive are light,
water, carbon dioxide, nitrogen, an phosphorous, However, scientists disagree on how
factors in the environment affect plant species richness. Three biologists discuss their
theories.
Biologist 1
The species richness of a plant community is determined by the amounts of available
resources. Plants compete for resources that are in short supply. As a result of
competition, no species attains high enough abundance to eliminate any other.
Therefore, a plant community with limited resources will have high species richness. To
explain species richness, it is necessary to examine the competitive relationships
between plant species.
Biologist 2
The species richness of a plant community is determined by the amounts of available
resources. When a resource is in short supply those species that are competitively
superior (use the resource most efficiently) increase in abundance. Eventually, these
dominant species become so abundant that some other species are eliminated,
resulting in lower species richness. A plant community with limited resources will be
composed of a few dominant species, each in high abundance, and some rare species
in low abundance. To explain species richness, it is necessary to examine dominant
species for the adaptations that allow them to acquire and use resources more
efficiently than rare species in an environment limited in resources.
Biologist 3
The species richness of a plant community is determined by the herbivores (plant-eating
animals) present. Herbivores encounter dominant species more often than rare
species. Consequently dominant species are eaten more often. A plant community will
be composed of many species because the abundances of dominant species are kept
low enough to allow the coexistence of species that would otherwise be eliminated. The
more herbivores present, the greater the chance of high plant species richness. To
explain species richness, it is necessary to examine the factors that affect the number of
herbivores.
1. Which of the following statements about the factors which affect species richness
would be consistent with the theories of biologist 1 and 2?
A
Competition has no effect on the species richness of plant communities.
B
The number of herbivores determines the species richness of plant communities.
C
The amounts of available resources determine the species richness of plant
communities.
D
The number of herbivores and the amounts of available resources both
determine the species richness of plant communities.
2. According to the theory of biologist 2, it can be concluded that when resources are
diminished
A
plant species richness increases.
B
plant species richness decreases.
C
no plant species occurs in high abundance.
D
competition between plant species decreases.
3. Which of the following is a criticism that Biologist 2 would make of the theory of
Biologist 1?
A
It ignores adaptations which make some plant species better competitors.
B
Plant species do not compete for limited resources.
C
Resources are never in short supply.
D
The role of herbivores is ignored.
4. In an experiment all of the herbivores in a plant community were removed. According
to the theory of Biologist 3, one would predict that the species richness of the plant
community would
A
increase, because the number of dominant species would increase.
B
increase, because rare species would increase in abundance and eliminate other
species.
C
decrease, because rare species would increase in abundance and eliminate
other species.
D
decrease because dominant species would increase in abundance and eliminate
other species.
5. Which of the following assumptions about herbivores was made by Biologist 3?
A
Herbivores have no effect on plant species richness.
B
Herbivores prefer to eat individual of rate plant species.
C
All plant species are equally preferred food sources for herbivores.
D
As the number of herbivores decreases, plant species richness increase.
6. The graph below shows the birth rate and death rate for a population during the
1900s.
From 1900 to 2000, the population has
A
increased.
B
decreased.
C
stayed the same.
D
increased until 1930, then decreased.
7. Rabbits introduced into Australia over 100 years ago have become a serious pest to
farmers. Rabbit populations increased so much that they displaced many native species
of plant eaters. What is the most logical explanation for their increased numbers?
A
Rabbits have a high death rate.
B
There are few effective predators.
C
There is an increase in rabbit competitors.
D
Additional rabbit species have been introduced.
8. The rate of growth of a natural population
A
always reaches the carrying capacity of the ecosystem.
B
is calculated by subtracting death rate from birth rate.
C
is limited by the carrying capacity of the ecosystem.
D
when graphed, always has a positive slope.
9. In a particular ecosystem, squirrels make up a large portion of the diet of coyotes. A
fatal disease in the squirrel population begins to reduce their population over a period of
months. Which graph best represents the expected changes in population size of the
coyotes and the squirrels?
A
B
C
D
graph 1
graph 2
graph 3
graph 4
10. Examine the population curves for wolves and moose in the graph below.
Which statement correctly describes the population relationship between the wolves
and moose from 1968 to 1973?
A
As the moose population increased the wolf population increased.
B
As the moose population increased the wolf population decreased.
C
As the wolf population decreased the moose population decreased.
D
As the wolf population increased the moose population decreased.
11. The graph below shows changes in the sizes of four animal populations over a 16year period.
In which population was birthrate most likely greater than death rate from year 8 to
year 12?
A
population 1
B
population 2
C
population 3
D
population 4
12. The size of a bird population increased by two percent in one year. Which of the
following could have contributed to the population increase?
A
a decrease in the death rate of baby birds
B
an increase in the number of the birds’ predators
C
an increase in the average number of parasites per bird
D
a decrease in the immigration of birds of the same species
13. The graph below shows changes in a yeast population over the course of several
days.
S
C10P47GGE43Q80606333
The yeast were placed on a nutrient dish and allowed to grow. On which day was
additional nutrient most likely added to the yeast culture?
A
day 3
B
day 4
C
day 6
D
day 7
14. Which graph shows a population of organisms that is closest to reaching the
carrying capacity of its environment?
15. Which variable is most likely to have the greatest positive effect on the growth of a
frog population?
A
a slight discoloration in female frogs
B
a shrunken voice box (larynx) in male frogs
C
a decrease in the number of lily pads in a frog pond
D
an increase in the number of insects around a frog pond
16. In a classic study of predator-prey interactions, the numbers of snowshoe hare
pelts and lynx pelts sold to a trading company by trappers were recorded over a period
of 100 years. Both lynx and hare populations appear to oscillate in a regular pattern
over a period of about ten years. One explanation for this pattern is that heavy predation
reduces the snowshoe hare population, which in turn reduces the lynx population. More
recently, scientists have proposed that the hare population oscillates due to diseases
caused by overcrowding or by the effects of its own feeding activities on vegetation.
What would prevent the lynx population from declining along with the hare population?
A
an extremely harsh winter
B
an influx of other hare predators
C
an abundant alternate food source
D
an outbreak of disease among hares
17. In 1970, scientists selected 100 species from each of three environments—ocean,
land, and freshwater. The graph below shows how many of these species still existed in
the year 2000.
Which statement best describes the trend represented by the data?
A
The ocean species increased in number.
B
There were more ocean species than land species.
C
The populations within each freshwater species decreased.
D
The numbers of land, freshwater, and ocean species all decreased.
18. The graph below shows how the number of bird species in a regenerating forest
changed over time.
Based on this information, which statement about the return of bird species to the
regenerating forest is correct?
A
The number of bird species changes as the forest regenerates.
B
It took six years for the bird species to return to the regenerating forest.
C
The total number of birds becomes more abundant as the forest regenerates.
D
The number of bird species is not as great now as it was before the forest began
regenerating.
19. Collared doves have a black half-collar, dark feathers, and a long, white-edged tail.
Until 1953, the collared dove had never been seen in the United Kingdom. The graph
below shows the population growth of the collared dove after it first arrived in the United
Kingdom.
Which of the following best explains why the curve flattens out at the X mark?
A
Predators could not catch the doves.
B
Food in the environment was limited.
C
Severe winters destroyed nesting sites.
D
The doves were able to find many mates.
20. This graph shows the sizes of lynx and hare populations between the years of 1845
and 1940.
If a predator of the lynx enters the food chain, you might expect the number of
A
lynx and hares to become equal
B
hares and lynx to decrease
C
hares to increase _
D
lynx to increase
21. Read the passage and study the data below.
A biology student performed an experiment to determine which of two
species of single-celled organisms would survive best when cultured
together in a certain environment. The student placed 10 organisms of
each species into a large test tube. Throughout the experiment, the
test tube was maintained at 30°C. After the test tube was set up, the
population of each species was determined each day for 5 days. The
data collected are shown in the table below.
The difference in the population sizes on the fifth day most likely resulted from
A
temperature changes.
B
variations in light intensity.
C
the buildup of nitrogen gas.
D
competition between species.
Use the data in the chart to answer the next two questions.
NUMBER OF PARAMECIA IN POND WATER SAMPLE
Day Species S Species T
1
50
50
2
60
80
3
100
90
4
150
60
5
160
50
6
160
30
7
160
20
22. Which of the following can be correctly concluded from the data?
A
Species S is the food for species T.
B
Species T is more common than species S.
C
Species S is a more successful competitor than species T.
D
Species T is a more successful competitor than species S.
23. Which of the following is the most likely outcome for Paramecia in the water
sample above?
A
Species T will probably die out.
B
Species T will move to a different pond.
C
Species S will continue to increase in number in order to provide food for Species
T.
D
Species S will feed on other organisms and allow Species T to increase in
number.
1. Community members hope to use a wetland area to attract tourists, especially
people interested in fishing and duck hunting. They had one big problem: mosquitoes.
To solve this problem they repeatedly sprayed insecticide that killed the mosquitoes and
destroyed the mosquito larvae. Comment on the solution to their problem.
A
Because the mosquito population was wiped out, the fish population increased
dramatically, attracting many fishermen to the area.
B
Although they killed the mosquitoes, they also killed the dragon flies and other
insects, eliminating one level of the wetland food web.
C
Because they were successful in killing all of the mosquitoes, their plan to attract
tourists went ahead as planned without additional problems.
D
Not only did the insecticide kill the mosquitoes, it killed all of the other insects in
the area, making this a great place for tourist to visit.
2. In a pond, the primary producer is a green alga, Spirogyra; the primary consumer is
the crustacean, Daphnia; the secondary consumer is a small fish, the bluegill; and the
tertiary consumer is a larger fish, the smallmouth bass. What changes can be expected
in the pond if the Daphnia are killed with pesticides?
A
The smallmouth bass population will die.
B
The Spirogyra population will probably die.
C
The bluegill population will probably increase.
D
The Daphnia population will eat something else.
3. One environmental problem caused by the use of nuclear power as an energy
source is the
A
disposal of wastes.
B
production of acid rain.
C
destruction of the ozone shield.
D
accumulation of CO2 in the atmosphere.
4. Which method of protecting members of an endangered species is most ecologically
sound?
A
protecting the habitats where these animals live from human development
B
passing laws that encourage hunting of the predators of these species
C
capturing these animals and putting them in wildlife parks
D
feeding and constructing shelters for these organisms
5. Large rebates and low-cost loans have been made available to homeowners to
install solar panels to heat their homes. The use of these incentives benefits
ecosystems because it
A
promotes the use of nonrenewable resources.
B
discourages the use of alternative energy.
C
encourages conservation of resources.
D
reduces the need for recycling.
6. Which statement best describes two effects of cutting down trees in rainforests?
A
Greenhouse gases decrease and less water is transpired.
B
Greenhouse gases decrease and more water is transpired.
C
Greenhouse gases increase and less water is transpired.
D
Greenhouse gases increase and more water is transpired.
7. Which of the following pictures best represents the natural greenhouse effect?
8. A developer purchases a piece of land where a deer population lives. How will the
deer population most likely be affected once the houses are built?
A
Birth rate will increase.
B
Death rate will decrease.
C
Population size will decrease.
D
Food availability will increase.
9. A recent study concluded that about 90% of all large predatory fish such as tuna
have disappeared from the world’s oceans in the past 50 years. Which of these is most
likely the direct cause of this loss?
A
climate change on Earth
B
acid precipitation over the oceans
C
urban development near the coast
D
commercial harvesting from the ocean
10. Rising ocean temperatures can cause corals to expel the symbiotic algae on which
they depend for survival. Which human influence could be responsible for an increase
in this phenomenon?
A
shoreline erosion
B
burning fossil fuels
C
solar power generation
D
introduction of non-native species
11. Which human activity is most responsible for the other three human activities?
A
increasing human population
B
increasing demand for food
C
increasing loss of farmland
D
increasing air pollution
12. A population of deer existed for centuries in a hilly region of England. The
landowners decided to introduce sheep into the same area. Deer and sheep eat some
of the same kinds of plants. After the sheep were introduced, the deer population began
to decline. How could the decline in the deer
population be explained?
A
Sheep competed with the deer.
B
The food web became too complex.
C
The sheep were smaller than the deer.
D
Sheep are at a higher trophic level than deer.
13. The burning of fossil fuels may contribute to an increase in global temperatures.
What might lead
to this increase in temperature?
A
Carbon dioxide in the atmosphere attracts solar radiation.
B
The combustion products allow more energy to enter the earth.
C
The combustion products reflect solar radiation away from Earth.
D
Carbon dioxide in the atmosphere blocks energy from escaping into space.
14. One way that pesticides have had a negative effect on ecosystems is by
A
building up toxins in animals that consume plants sprayed with pesticides.
B
making plants that have been sprayed with pesticides unable to fix nitrogen in
soil.
C
preventing runoff from fields sprayed with pesticides from entering lakes and
streams.
D
allowing plants that have been sprayed with pesticides to build up resistance to
the pesticides.
15. A builder is proposing a new housing development in an area of western
Massachusetts. Construction of the housing development will destroy the wetland
habitat in the area.
Which of the following would be the most likely consequence of the wetland’s
destruction?
A
The wetland plant species would disperse to adjacent meadow habitats.
B
The populations of wetland animals would be unable to survive in that area.
C
The wetland animal species would survive by interbreeding with non-wetland
species.
D
The populations of wetland plants would evolve to disperse seeds by wind rather
than water.
16. Which of the following human activities reduces biodiversity?
A
prohibiting hunting in wildlife preserves
B
taking tissue samples from members of endangered species
C
planting only native grass species to prevent erosion beside highways
D
planting only red pine trees to replace native hardwood forests cut for lumber
17. Which change most likely caused a decrease in global mean surface temperatures
during the time periods shaded on the graph?
A
B
C
D
an increase in deforestation
an increase in the use of fossil fuels
an increase in volcanic eruption emissions
an increase in the population of domesticated livestock
18. Geothermal energy can be converted from hot water or steam from deep within
Earth’s surface and transformed into electricity. One disadvantage of geothermal energy
is that
A
it is a nonrenewable resource.
B
emitted toxins can gather in animals.
C
habitats can be destroyed when drilling.
D
it releases hazardous waste into the atmosphere.
19. Manufacturers in the United States have eliminated chlorofluorocarbons from
common household aerosol products. This has reduced their contribution to which
environmental problem?
A
acid rain
B
desertification
C
global climate change
D
atmospheric ozone depletion
20. Increased reliance on which energy source would likely have the most negative
effects on global climate change?
A
coal
B
wind
C
nuclear
D
hydroelectric
21. At which point did greenhouse gases first begin to affect temperatures on Earth?
A
when the first land plants appeared on Earth
B
when the atmosphere first formed on Earth
C
after the hole formed in the ozone layer
D
after humans started using fossil fuels
22. The Mississippi Department of Wildlife and Fisheries is making an artificial reef in
the Gulf of Mexico. How will this most likely affect the fish population?
A
The fish population will have more diseases.
B
The fish population will increase in numbers.
C
The fish population will become endangered.
D
The fish population will be unaffected by reefs.
23. In one study, scientists found that the number of raccoons increased where people
built homes in their habitats. Which of the following is most likely the reason why the
number of raccoons increased?
A
Raccoons no longer lived in wild areas.
B
Raccoons found more food living near humans.
C
More predators of raccoons live near people’s homes.
D
People destroyed raccoon habitats when they built homes.
24. By causing atmospheric changes through activities such as polluting and careless
harvesting, humans have
A
affected global stability in a positive way.
B
established equilibrium in ecosystems.
C
caused the destruction of habitats.
D
replaced nonrenewable resources.
25. A major reason that humans can have such a significant impact on an ecological
community is that humans
A
reproduce faster than most other species.
B
can modify their environment through technology.
C
remove large amounts of carbon dioxide from the air.
D
are able to increase the amount of finite resources available.
26. Which method of fly control would be most harmful to other organisms in the
environment?
A
using fly traps
B
planting carnivorous plants
C
releasing sterilized male flies
D
spraying broad-range insecticides
27. The graph below shows how atmospheric carbon dioxide levels have changed
since 1958.
Which factor most likely explains why the amount of atmospheric carbon dioxide
fluctuates within each year?
A
the addition of carbon dioxide to the atmosphere from factories
B
the addition of carbon dioxide to the atmosphere from cars
C
seasonal changes in photosynthesis
D
seasonal melting of Arctic ice caps
28. The diagrams below show the ozone level over Antarctica in October 1979, 1988,
and 1996.
Which conclusion about the ozone level over Antarctica from 1979 to 1996 is best
supported by these diagrams?
A
It has stayed the same.
B
It has continually increased.
C
It has continually decreased.
D
It has sometimes increased and sometimes decreased.
29. Study the model below.
Which phenomenon does this model explain?
A
El Nino
B
ozone buildups
C
cloud formation
D
greenhouse effect
30. Your teacher gives you 10 years of population data for two animal species in
Tennessee. You learn the species have a predator-prey relationship. Your teacher
instructs you to develop a model of the population changes. You use your computer to
begin creating the graph shown below.
Which graph below correctly adds the predator population?
33. Use the graph below to answer the question that follows.
Which of the survivorship curves displayed on the graph above is characteristic of
humans in modern industrialized countries?
A
curve I
B
curve II
C
curve III
D
curve IV
31. Planaria are flatworms that are found in shallow streams, often attached to the
bottoms of rocks. A class is studying a population of planaria in a nearby shallow
stream. The graph below shows data collected over 11 weeks.
The population started to decrease after 5 weeks. The students concluded that the
stream did not have enough food to support a large population of planaria. If this trend
continues, how many planaria will be living in the stream by the 12th week?
A
600
B
500
C
400
D
300
32. The rate of growth of a natural population
A
when graphed, always has a positive slope.
B
is limited by the carrying capacity of the ecosystem.
C
is calculated by subtracting death rate from birth rate.
D
always reaches the carrying capacity of the ecosystem.
33. In the past decade, which of the following has not been a major cause of the
increase in the world's population?
A
longer life span
B
lower infant mortality
C
increase in birth rate
D
improved sanitation
E
modern preventative medicine
34. Based on the graph below, what is the best explanation for the change in the deer
population between years 2 and 6?
A
B
C
D
There was limited predation of the deer.
Some deer left the area due to overcrowding.
The competition within the population for the resources increased.
The number of births equaled the number of deaths in the population.
35. The graph below shows changes in a caribou population over time.
Based on the graph, which of the following is a possible explanation for the stabilization
of the caribou population?
A
an equal number of deaths and births
B
an unequal number of deaths and births
C
an equal number of immigrants and births
D
an unequal number of immigrants and deaths
1. In an ecosystem, which is the most likely reason for an increase in the producer
population if there is an increase in the carnivore population?
A
less food
B
more oxygen
C
fewer herbivores
D
higher temperatures
2. Certain organisms are able to store energy from the sun in energy-rich compounds.
Which event best illustrates this activity?
A
A caterpillar is eaten by a blackbird.
B
Lettuce produces organic substances.
C
A fox captures and eats a young rabbit.
D
Bacteria change organic material into simple nutrients.
3. A partial food web for organisms in Yellowstone National Park is shown below. Use
this food web to answer the following two items.
Which of the following organisms is a secondary consumer in this food web?
A
yellow-bellied marmot
B
strawberry plant
C
least chipmunk
D
king bolete
4. Which of the following releases oxygen into this food web ecosystem?
A
elk respiration
B
Idaho fescue photosynthesis
C
sweet cicely root decomposition
D
migratory grasshopper reproduction
5. The diagram below shows a food web.
Each number represents an organism in the food web. Which of these organisms can
transform light energy into chemical energy?
A
organism 1
B
organism 3
C
organism 6
D
organism 9
6. The diagram below represents a model of a food pyramid.
Which statement best describes what happens in this food pyramid?
A
Energy is lost to the environment at each level, so less mass can be supported at
each higher level.
B
More organisms die at higher levels than at lower levels, resulting in less mass at
higher levels.
C
Organisms decay at each level, and thus less mass can be supported at
succeedingly higher levels.
D
When organisms die at higher levels, their remains sink to lower levels,
increasing the mass of lower levels.
7. The diagram below shows an energy pyramid for a forest ecosystem.
What do the sizes of the levels in the energy pyramid represent?
A
the amount of energy recycled by the organisms at each level
B
the amount of energy available in the organisms at each level
C
the amount of energy used daily by the organisms at each level
D
the amount of heat given off daily by the organisms at each level
8. Study the energy pyramid below.
Which graph best represents the relative energy content of the levels of this pyramid?
A
B
C
D
graph 1
graph 2
graph 3
graph 4
9. Study the food web below.
How would a decrease in the number of herring most likely affect the amount of energy
available for the other organisms?
A
There would be more energy available for the phytoplankton.
B
There would be less energy available for the baleen whales.
C
There would be more energy available for the zooplankton.
D
There would be less energy available for the seals.
10. In the diagram, which organism provides nutrients for the largest number of other
organisms?
A
B
C
D
Herring
Snapper
Bluefish
Seal
11. Use the information below to answer the question that follows.
The diagram above shows a biomass pyramid for a type of ecosystem. Based on the
shape of its biomass pyramid, this ecosystem is most likely to have which of the
following characteristics?
A
The producers reproduce, grow, and are consumed very rapidly.
B
Decomposers feed directly on the ecosystem's producers.
C
Energy transfer between trophic levels is highly efficient.
D
A single producer can sustain many primary consumers.
12. Use the diagram with Food Web A and Food Web B for the following two items.
Look at FOOD WEB A.
Only two animals in this food web have three direct (immediate) food sources. Which
two animals are they?
A
Parasitic Wasp and Spider
B
Native Cat and Butcher Bird
C
Native Cat and Parasitic Wasp
D
Parasitic Wasp and Leaf Hopper
13. Food webs A and B are in different locations. Imagine if Leaf Hoppers died out in
both locations. Which one of these is the best prediction and explanation for the effect
this would have on the food webs?
A
The effect would be greater in food web A because the Parasitic Wasp has only
one food source in web A.
B
The effect would be greater in food web A because the Parasitic Wasp has
several food sources in web A.
C
The effect would be greater in food web B because the Parasitic Wasp has only
one food source in web B.
D
The effect would be greater in food web B because the Parasitic Wasp has
several food sources in web B.
14. White-tailed deer meet their energy needs through which of these activities?
A
eating plants
B
drinking water
C
absorbing sunlight
D
exhaling carbon dioxide
15. A food web is shown below.
If the rabbit population increases, which of the following is most likely to happen soon
afterward?
A
The deer population will increase.
B
The plant population will decrease.
C
Different birds will move into the area.
D
The insect population will be eliminated.
16. The diagram below shows a simplified food pyramid.
The number of organisms is generally smaller at the top than at the bottom because
organisms at the top usually
A
adapt more quickly.
B
have more offspring.
C
have more predators.
D
require more energy.
17. A student has set up an artificial ecosystem for a class project. This ecosystem has
producers, first-level consumers, second-level consumers, and third-level consumers.
By accident, a chemical enters the ecosystem and kills all of the first-level consumers.
Which group(s) of organisms will most likely survive?
A
producers
B
second-level consumers
C
second-level and third-level consumers
D
third-level consumers and producers
2546; GS0000LSFXC0872A
18. Which of the following organisms is not ultimately dependent on the sun as a
source of energy?
A
An underground earthworm avoids the sun.
B
All of the choices ARE ultimately dependent on the sun.
C
A night-blooming flower is pollinated by night-flying bats.
D
All of the choices are NOT ultimately dependent on the sun.
19. Which organism in the aquatic food web below gets energy directly from the Sun?
A
B
C
D
krill
baleen whale
phytoplankton
both krill and the baleen whale
20. Leaves fall from deciduous trees in autumn. The carbon in these leaves is returned
to the atmosphere through which of the following processes?
A
transpiration
B
condensation
C
decomposition
D
photosynthesis
21. A marine food web is shown below.
Which of the following diagrams correctly represents an energy pyramid from this web?
22. The food web shows the interactions between organisms in a meadow ecosystem.
Which
food energy directly from both plants and animals?
A
fox
B
grass
C
snake
D
grasshopper
organism gets
23. The diagram shows a food web in a large park.
Each circle represents a different species in the food web. Which of the organisms in
the food web could be referred to as primary consumers?
A
7 only
B
5 and 6 only
C
2, 3, and 4 only
D
2, 5, and 7 only
24. Certain organisms are able to store energy from the sun in energy-rich compounds.
Which events best illustrate this activity? Select two options.
A
A caterpillar is eaten by a blackbird.
B
Maple trees produce and store sap.
C
A spider produces silk to spin a web.
D
Lettuce produces organic substances.
E
A fox captures and eats a young rabbit.
F
Bacteria change organic material into simple nutrients.
The next question has two parts. Answer part A, and then answer part B.
Study the food web below.
25. Part A. Which of the following organisms is a secondary consumer in the food
web?
A
yellow-bellied marmot
B
strawberry plant
C
least chipmunk
D
king bolete
26. Part B. Based on the correct answer in Part A, if the population of this organism
declines rapidly which of the following will most likely occur as a result of this decline?
A
The grizzly bear population will decrease.
B
The Idaho fescue population will increase.
C
The soil bacteria population will decrease.
D
The migratory grasshopper population will increase.
27. The diagram above represents an energy pyramid from a stable environment.
If energy numbers were added to each trophic level of this pyramid the numbers would
A
increase from A to D
B
decrease from A to D
C
increase from D to A
D
decrease from D to A
1. This diagram shows the flow of carbon in a terrestrial ecosystem.
Atmosphere
Consumer
Producer
Decomposer
Which will most likely happen if the decomposers are removed from the carbon cycle?
A
The amount of carbon dioxide in the atmosphere will increase.
B
The amount of carbon dioxide in the atmosphere will decrease.
C
The amount of carbon dioxide used by producers will increase.
D
The amount of carbon dioxide needed by consumers will decrease.
2. Over 6 billion people on Earth use water every day, yet Earth’s water supply remains
relatively constant. This is because
A
the sea level is rising.
B
water exists in three phases on Earth.
C
water is constantly recycled by the hydrologic cycle.
D
global warming melts ice to replace water that is used.
3. A sealed terrarium that contains soil, plants, and a small bowl of water is placed in a
window. If the intensity of solar energy reaching the terrarium through the window is
increased by 10%, how would the water cycle within the terrarium most likely be
affected?
A
The rate of evaporation would increase.
B
The temperature of the soil would decrease.
C
The total amount of water vapor would decrease.
D
The amount of oxygen gas in the air would increase.
4. Which of these changes would most likely increase crop productivity in a farmland
area?
A
introducing non-native insect species to the area
B
removing predators from the food web in the area
C
reducing the atmospheric carbon dioxide present in the area
D
increasing the population of nitrogen fixing bacteria in the area
00-2131A
5. Nitrogen-fixing bacteria help cycle nitrogen through ecosystems. How do they do
this?
A
They change nitrogen into forms usable by plants.
B
They convert water and carbon dioxide into sugar.
C
They release the chemical energy in nitrogen for respiration.
D
They convert sunlight into chemical energy stored in nitrogen.
6. The possibility that some of the water you use today may have washed onto a beach
millions of years ago can be explained on the basis of the water cycle. Which of the
following best illustrates the water cycle? (Note: the arrows show the direction that the water is
moving through the water cycle.)
A
B
C
D
snow —> water vapor —> hail —> soil —> snow
snow —> clouds —> sunshine —> snow —> rain
rain —> runoff —> lake —> water vapor —> rain
rain —> sunshine —> hail —> water vapor —> sleet
7. The diagram shows a simplified nitrogen cycle.
Which process is responsible for returning nitrogen to the air?
A
excretion
B
nitrification
C
decomposition _
D
photosynthesis
8. Which of the following explains why legume plants are less likely than other
terrestrial plants to experience nitrogen limitation?
A
Legume plants need less nitrogen than other plants do.
B
Legume plants have nitrogen-fixing bacteria on their roots.
C
Legume plants catch insects to supply themselves with nitrogen.
D
Legume plants can absorb nitrogen directly from the atmosphere.
9. During a hot, dry month, which water cycle process happens most often?
A
runoff
B
rainfall
C
gas changing to liquid
D
liquid changing to gas
10. Which process does not need to occur for water to cycle through the environment?
A
water condensing
B
water evaporating
C
oxygen being dissolved in water
D
energy being transferred from the Sun
11. The global water cycle consists of water circulating among the land, the
atmosphere, the oceans, and organisms. Where do trees get most of their water directly
from?
A
streams
B
lakes
C
soil
D
air
12. The water cycle would not occur if which of the following were missing?
A
animals
B
bacteria
C
ice caps
D
solar energy
13. It will take the longest time for the hydrologic cycle to replace water that has been
used in which of the following ways?
A
A city withdraws water from a reservoir to supply homes and businesses.
B
Farmers pump water from an underground aquifer to irrigate their fields.
C
A cloud-seeding airplane causes rain to fall over an agricultural area.
D
Village residents catch rainwater in basins and use it for washing.
14. A carrot plant is exposed to carbon dioxide containing radioactive carbon for 24
hours. After this exposure, the carrot roots are found to have accumulated radioactivity.
These carrots are then fed to a rabbit. One week later, the rabbit's tissue is tested for
radioactivity and is found to have a higher than normal background count. Which
biogeochemical cycle is apparent from this study?
A
water
B
carbon
C
oxygen
D
nitrogen
15. Local environmental scientists have collected evidence of the presence of
insecticides in the river. Insecticides are used on crops to help prevent damage from
insects.
According to the diagram, how might this insecticide have reached the river?
A
transpiration
B
precipitation
C
condensation
D
surface runoff
16. Planting additional legumes in the area shown below would most likely lead to
which of the following?
A
B
C
D
a decrease in the activity of bacteria
a decrease in the number of animals in the area
an increase in the activity of nitrogen-fixing bacteria
an increase in the number of species that can fix nitrogen
17. The diagram shows several phases of the nitrogen cycle.
Which of the following describes the most likely effect of removing some plants from the
area by using chemical herbicides?
A
The flow of necessary nutrients would be disrupted.
B
The infiltration of water into the ground would be halted.
C
The rate of erosion of rocks on the ground would be slowed.
D
The ability of plants to complete photosynthesis would be increased.
18. The global water cycle consists of water circulating among the land, the
atmosphere, the oceans, and organisms. Where do trees get most of their water directly
from?
A
air
B
soil
C
lakes
D
streams
19. The water cycle would not occur if which of the following were missing?
A
animals
B
bacteria
C
ice caps
D
solar energy
20. It will take the longest time for the hydrologic cycle to replace water that has been
used in which of the following ways?
A
A city withdraws water from a reservoir to supply homes and businesses.
B
Farmers pump water from an underground aquifer to irrigate their fields.
C
A cloud-seeding airplane causes rain to fall over an agricultural area.
D
Village residents catch rainwater in basins and use it for washing.
21. A carrot plant is exposed to carbon dioxide containing radioactive carbon for 24
hours. After this exposure, the carrot roots are found to have accumulated radioactivity.
These carrots are then fed to a rabbit. One week later, the rabbit's tissue is tested for
radioactivity and is found to have a higher than normal background count. Which
biogeochemical cycle is apparent from this study?
A
water
B
carbon
C
oxygen
D
nitrogen