Name _________________________
Date ___________________ Per ___
Unit 5 – Plants and Animals are Interdependent
1. The diagram below illustrates the relationship between organisms in an ecosystem.
In addition to sunlight, which factor would need to be
added to make this a stable ecosystem?
A. predators
C. decomposer
B. prey
D. herbivores
2. One artic food chain consists of polar bears, fish, seaweed, and seals. Which sequence demonstrates the correct flow of
energy between these organisms?
A. seals→seaweed→fish→polar bears
B. fish→seaweed→polar bears→seals
C. seaweed→fish→seals→polar bears
D. polar bears→fish→seals→seaweed
3. In an ecosystem, the herring population was reduced by fisherman. As a result, the tuna, which feed on the herring,
disappeared. The sand eels, which are eaten by herring, increased in number. The fisherman then overharvested the sand
eel population. Cod and seabirds then decreased. Which food web best represents the feeding relationships in this
ecosystem?
A.
B.
C.
D.
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Date ___________________ Per ___
4. In an ecosystem, the growth and survival of organisms are dependent on the availability of the energy from the
Sun. This energy is available to organisms in the ecosystem because
A. producers have the ability to store energy from light in organic molecules.
B. consumers have the ability to transfer chemical energy stored in bonds to plants.
C. all organisms in a food web have the ability to use light energy.
D. all organisms in a food web feed on autotrophs.
5. Base your answer to the following question on the diagram below, which represents a pond food web, and on your
knowledge of biology.
Which energy pyramid most accurately shows the energy
relationships between three organisms in this food web?
A.
B.
C.
D.
6. Base your answer to the following question on the diagram above in #5, which represents a pond food web, and on your
knowledge of biology.
Which statement best describes what will most likely happen if the amphipod population is removed from this food web?
A. Population sizes of species at feeding levels both before and after amphipods will decrease.
B. Population sizes of species at feeding levels both before and after amphipods will increase.
C. Population sizes of species at feeding levels after amphipods will increase and before amphipods will decrease.
D. Population sizes of species at feeding levels after amphipods will decrease and before amphipods will increase.
7. Which of these organisms could most likely be found at the top of an energy pyramid?
A. clams
B. sardines
C. sharks
D. kelp
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Date ___________________ Per ___
8. Base your answer to the following question on the information and graph below and on your knowledge of biology.
A population of paramecia (single celled aquatic organisms) was grown in a 200 -mL beaker of water containing
some smaller single celled organisms. Population growth of the organisms for 28 hours in shown in the graph
below.
Which factor most likely accounts for
the change in the paramecium population form
8 to 20 hours?
A. an increase in the nitrogen content
of the water
B. an increase in wastes produced
C. an increase in available food
D. an increase in water pH
9. Scientists have been concerned about the reduction of shark populations due to overfishing off the east coast of the
United States. Sharks feed on rays, which feed on scallops. Scallops feed on microscopic algae, which they filter from
seawater. Without sharks, the rays consume and eliminate scallop beds, harming the scallop fishing industry. This
situation demonstrates that
A. sharks are not important for the stability of this ecosystem.
B. reducing the shark population increases the quantity of scallops that can be harvested.
C. humans can upset ecosystem stability by removing species.
D. humans improve ecosystems diversity by removing predators.
10. The picture below shows an energy pyramid.
What will most likely happen to the
foxes and the wolves if the rabbits are
removed?
A. The foxes will eat more wolves.
B. The foxes will eat fewer wolves.
C. There will be more foxes and
wolves.
D. There will be fewer foxes and
wolves.
Name _________________________
Date ___________________ Per ___
11. The picture below shows an ocean bay food chain.
Sea otters move into the
ocean bay. They eat all
the sea urchins. This
change will cause the
A. kelp to have less food.
B. crabs to have more food.
C. sea ducks to have less food.
D. arctic foxes to have more food.
12. Ecosystems are composed of all living and nonliving components in an area. Food webs show the flow of nutrients
and energy within an ecosystem.
Use the food web to answer the following question.
`
Suppose that a new predator of the rabbit migrated to this
ecosystem. What is the most likely initial effect on the other
organisms?
A. More competition among the mice for food
B. More competition among the hawks for food
C. Less competition among snakes for food
D. Less grass available for food
13. Use the diagram below to answer the question.
In this energy pyramid, which organism would most likely be in level 2?
A. bird
B. fox
C. caterpillar
D. tree
14. Which food chain correctly summarizes the flow of energy through an ecosystem?
A. sun→rabbit→grass→fox
B. rabbit→fox→sun→grass
C. fox→sun→rabbit→grass
D. sun→grass→rabbit→fox
Name _________________________
Date ___________________ Per ___
15. Use the food chain below to answer the following question.
What do the arrows in the food chain indicate about the flow of
energy in an ecosystem?
A. Energy is continuously recycled by the organisms in an
ecosystem.
B. Energy flows in one direction in an ecosystem, from producers to
consumers.
C. More of the available energy in an ecosystem is given to large
animals than to small animals.
D. Organisms at the end of the food chain receive more energy than
those at the beginning.
16. Which diagram correctly shows the direction of energy flow through a food web?
A.
C.
B.
D.
17. Use the food chain to answer the question about the food chain shown below.
In which part of the food chain is the greatest amount of energy transferred?
A. from the grass to the insect
B. from the insect to the frog
C. from the frog to the owl
D. from the owl to the hawk
Name _________________________
Date ___________________ Per ___
18. Lightning from a thunderstorm strikes a tree that falls to the forest floor and dies. During the next few years the dead
tree undergoes many changes.
What organisms are most likely responsible for the biological and chemical changes to the tree?
A. consumers
B. decomposers
C. predators
D. producers
19. 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
20. The diagram below shows an energy pyramid.
A. 10 kcal/m²/year
B. 100 kcal/m²/year
C. 1,000 kcal/m²/year
D. 5,000 kcal/m²/year
21. Which of the following lists identifies organisms that are producers in food webs?
A. algae, ferns, sunflowers
B. mushrooms, bacteria, earthworms
C. termites, red foxes, shrews
D. woodpeckers, cardinals, grasshoppers
22. Which best determines the number of wolves that can live in an area?
A. the amount of snow in the area each year
B. the number of birds that live in the area
C. the number of trees in the area
D. the amount of food available in the area
Name _________________________
Date ___________________ Per ___
23. A simple diagram of nutrient cycling is shown below.
What substances do X and Y represent in this nutrient cycle?
A. Substance X is salt and substance Y is water.
B. Substance X is glucose and substance Y is starch.
C. Substance X is nitrogen and substance Y is ammonia.
D. Substance X is carbon dioxide and substance Y is oxygen.
24. The diagram below shows the flow of energy through the organisms in a Maryland river. Use the chart below to
answer the following question.
If the trout were overfished, which
population of organism would most likely
increase as a direct result?
A. algae
B. minnows
C. trout
D. zooplankton
25. The energy pyramid below shows the flow of energy through the organisms in a kelp forest ecosystem in the Pacific
Ocean. Use the energy pyramid to answer the following question.
How would the populations of
other organisms in the energy
pyramid be affected if the
population of sea urchins suddenly
decreased?
A. Both the kelp and the sheephead
populations would increase.
B. Both the kelp and the sheephead
populations would decrease.
C. The kelp population would
decrease, and the sheephead
population would increase.
D. The kelp population would
increase, and the sheephead
population would decrease.
Name _________________________
Date ___________________ Per ___
26. Use the information below to answer the following question.
The gypsy moth was accidentally brought into the United States. The caterpillars of these moths eat the leaves of
hardwood trees. Eating these leaves decreases the growth of the trees and may cause the trees to die. A gypsy moth and
gypsy moth caterpillar are pictured below.
Why do gypsy moth caterpillars eat leaves?
A. to destroy the hardwood tree
B. to extract energy for growth
C. to obtain trapped oxygen
D. to produce their own food
27. The diagram below shows a food chain in a garden environment.
Which statement describes the energy
transfer in this food chain?
A. The energy from the bird is transferred back to the grasshopper.
B. The grass passes all of the energy it receives from the sun to the grasshopper.
C. Only a small amount of the energy the bird receives from the grasshopper is used by the bird.
D. More energy is transferred from the grass to the grasshopper than from the grasshopper to the bird.
28. The figure below shows the flow of energy through an ecosystem. Plants and animals can be classified based on their
position within the flow of energy through an ecosystem. Producers, such as green plants, convert light energy from the
sun into chemical energy. Plants use this energy for
survival; this energy is also used by first-level consumers,
such as cows, when they eat producers, and so on.
Rabbits eat plants. Accordingly, rabbits belong to which of
the following groups?
A. producers
B. first-level consumers
C. second-level consumersD. decomposers
29. Which of the following groups receives energy directly from all other groups?
A. producers
B. first-level consumers
C. second-level consumers
D. decomposers