7th grade, Ecology
2008
1. What is the original source of energy for all organisms in an energy pyramid?
a. Carbon dioxide
b. Sunlight
c. Soil
d. Water
2. Based on the following information, which food chain is most probable?
Trout – a carnivorous fish
Minnow – an herbivorous fish
Algae – microscopic, photosynthetic organism
Osprey – a large carnivorous bird
a.
b.
c.
d.
Trout
Algae
Minnow
Algae
Osprey
Trout
Algae
Minnow
Algae
Minnow
Trout
Trout
Minnow
Osprey
Osprey
Osprey
3. Two fish-eating, cliff-nesting birds (the cormorant and the shag) are both able to live in the
same area because they are able to occupy ___________________.
a. the same habitat and the same niche
b. the same habitat but different niches
c. different habitats but the same niche
d. neither the same habitat nor the same niche
4. Which of the following statements about ecosystems is correct?
a. An ecosystem can exist with or without a constant source of energy input.
b. An ecosystem must contain consumers but can exist without producers.
c. An ecosystem involves interactions between biotic and abiotic factors.
d. An ecosystem can exist on land but cannot exist in lakes, rivers or oceans.
5. Why does each successive level in an energy pyramid contain less energy?
a. Most energy taken up by a level is lost before being transferred up.
b. The producer level processes the most energy of any level.
c. The highest levels lose the most energy.
d. Carnivores process much less energy than any other level.
6. Why does each successive level in an energy pyramid have fewer individual organisms?
a. Top consumers are very large individuals.
b. Large herbivores are not very abundant.
c. Energy loss between levels is too great to support more organisms above.
d. Organisms at the highest levels are so large that there is no energy left.
7. The first or lowest level organism in most food webs is a(n) _____________.
a. carnivore
b. decomposer
c. herbivore
d. producer
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7th grade, Ecology
2008
8. Use the diagram of the aquarium below. Which statement is correct?
a.
b.
c.
d.
The community within this ecosystem consists of seven guppies and one catfish.
The energy source for this ecosystem is the gas from the air stone.
A population within this ecosystem is the three snails.
The guppies and snails occupy the same niche.
9. Streams that feed a pond dry up and the pond therefore dries up too. The pond is
surrounded by a beech/maple forest. What will likely happen to the pond area if the streams
stay dry for another year?
a. A beech maple forest will replace the former pond.
b. The area previously covered by a pond will not change.
c. The pond area will fill in with sediment.
d. Vegetation will start to grow in the former pond area.
10. The chart below lists four groups of factors relating to an ecosystem.
Group A
Sunlight
Green plants
Rainfall
Consumers
Gases
Group B
Sunlight
Climate
Rainfall
Minerals
Gases
Group C
Sunlight
Green plants
Rainfall
Consumers
Gases
Group D
Sunlight
Rainfall
Consumers
Producers
Water
Which group contains only abiotic factors?
a.
b.
c.
d.
Group A
Group B
Group C
Group D
11. Which 2 factors are abiotic limiting factors that affect organisms in a desert biome?
a.
b.
c.
d.
Little rainfall and wide variation in daily temperature
Few producers and not a lot of shade
Below freezing cold nights and wet days
Sand storms and courtship behavior
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7th grade, Ecology
2008
12. Which statement best explains section X of the graph?
a.
b.
c.
d.
Biotic factors became more important than abiotic factors.
Immigration began to exceed emigration.
A decrease in the birth rate may have occurred.
More food became available to the bird population.
13. The diagram represents an energy pyramid. At each successive trophic level from A to D,
the amount of energy available to the next higher level
a.
b.
c.
d.
increases
decreases
increases, then decreases
remains the same
14. This graph shows how the numbers of predator (the paramecium) and prey (yeast cells)
change over time. Why does a predator population minimum occur on days 5 and 12?
a.
b.
c.
d.
There were too many prey in the preceding few days.
A limiting factor has become important.
The predator population responds only to excess numbers of prey.
The population of prey is rising, but not quite fast enough.
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7th grade, Ecology
2008
Base your answers to questions 15 and 16 on the information below:
Analysis of a sample taken from a pond showed variety in both number and type of organisms
present. The data collected are shown in the table below.
Data Table
Number Present
Type of Organisms
Frogs
40
Bass
2
Phytoplankton
1000’s
Insect larvae
100’s
15. If the frogs feed on the insect larvae, what is the role of the frogs in this pond ecosystem?
a. Herbivore
b. Parasite
c. Consumer
d. Host
16. Which diagram best represents the organisms arranged as an energy pyramid?
A.
C.
Bass
B.
Phytoplankton
Frogs
Insect Larvae
Insect Larvae
Frogs
Phytoplankton
Bass
Bass
D.
Insect Larvae
Insect Larvae
Phytoplankton
Frogs
Frogs
Phytoplankton
Bass
17. Several years after a building was torn down and the ground cleared, grasses were the first
things to thrive in the area for several years because
a. Predators could not find suitable habitat there when it was bare.
b. The soil characteristics could not yet support bushes or trees.
c. Producers must be present first before any herbivores or carnivores.
d. There were too many open, unoccupied niches in the area for consumers.
18. Which statement best explains why a food web is a more realistic representation of
nutritional patterns than a straight food chain?
a.
b.
c.
d.
Energy always flows from the consumers to the producers.
The amount of energy available at each higher trophic level increases.
Most carnivores only consume individuals from one species of organism.
Practically all species are consumed by or feed on more than one species.
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7th grade, Ecology
2008
19. What would be a direct effect in the community below if the wolves and the mountain lions
were removed?
a.
b.
c.
d.
There would be fewer hawks.
There would be more grass and trees.
There would be more moose and elk.
There would be no change in the community.
20. Long-term environmental change includes all of the following EXCEPT
a. normal increasing amounts of wind during springtime each year.
b. having fewer herbivores with each passing year.
c. more deer each year.
d. slightly warmer average temperatures each year.
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7th grade, Ecology
2008
Answer Key:
1. b
2. d
3. b
4. c
5. a
6. c
7. d
8. c
9. d
10. b
11. a
12. c
13. b
14. c
15. c
16. a
17. b
18. d
19. c
20. a
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