3rd Grade Ecosystems
Read and answer each question carefully.
1)
2)
3)
4)
What must be included in every food web and food chain?
A)
grass
B)
coyotes
C)
sun
D)
people
Plants make food energy for other organisms. Plants are called
A)
decomposers.
B)
consumers.
C)
producers.
D)
ecosystems.
All plants and animals
A)
live in a balanced ecosystem.
B)
have less growth.
C)
are part of only one food chain.
D)
cause changes to their ecosystem.
Another word for any living thing is
consumer.
B) organism.
C) animal.
D) plant.
A)
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5)
6)
7)
Living organisms interact with
A)
only nonliving things in the environment.
B)
only things that they choose to interact with.
C)
both living and nonliving things in the environment.
D)
only other living things in the environment.
Most animals in a food web would eventually die if
A)
plants could not make food from the sun.
B)
if plants grew too tall.
C)
they hibernated in the winter.
D)
there wasn’t enough grass to eat.
Which of these is an interaction between a living thing and a non-living thing?
A)
An animal eats a plant.
B) Water is in the ocean.
8)
C)
Soil is under a rock.
D)
An animal is drinking water.
What is the source of energy for living things on Earth?
A)
sun
B)
consumers
C)
decomposers
D)
producers
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9)
Energy flows through a food chain when
A) an animal builds a shelter.
B) an animal plays with another animal.
C) an animal eats another animal.
D) an animal runs away from another animal.
10)
Which is a harmful interaction for a plant in an ecosystem? A) Small rocks are in the soil.
B) The climate is hot.
C) The weather is warm.
D) Water is removing soil from the roots.
11)
A group of animals who get their energy from dead plants and animals are called
A) producers.
B) organisms.
C) plants.
D) decomposers.
12)
Some organisms are called consumers because they
A) eat other organisms for energy.
B) get food from a web.
C) use the soil for food.
D) are not in a food chain.
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13)
Which is a living resource for a mouse?
A) good climate
B) tall grass
C) clean air
D) large space
14)
All living and non-living things in the environment that an organism needs and
uses to survive are called:
A) food
B) minerals
C) resources
D) plants
15)
When there is plenty of food, water, and space in an ecosystem, what is most
likely to happen to the number of animals in that animal population? The number
of animals will
A) decrease.
B) stay the same.
C) increase.
D) go up and down.
16)
A student observed a cross-section of a tree. He knew that narrow rings showed
that the tree had harmful interactions with its environment. What might have
caused the narrow rings?
A) other plants
B) rocks nearby
C) not enough rain
D) good weather
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17)
If an ecosystem changes and the needs of a plant cannot be met by its
environment, the plant will most likely
A) die.
B) survive.
C) reproduce.
D) change or move.
18)
What would be a harmful interaction between two living things?
A) An animal eats all the plants.
B) Rocks fall into the water.
C) The air becomes cooler.
D) The soil is wet by water.
19)
Which of these is true about ecosystems?
A) Small ecosystems are best.
B) Scientists never study ecosystems.
C) Ecosystems are changed by organisms.
D) Large ecosystems are never balanced.
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Use the following graphs to answer questions 20 and 21.
20)
Which graph shows the changes to a wolf population in a balanced ecosystem?
A) Graph 1
B) Graph 2
C) Graph 3
D) Graph 4
21)
Which graph shows what might happen to a wolf population when the wolves
cannot meet their needs in the ecosystem?
A) Graph 1
B) Graph 2
C) Graph 3
D) Graph 4
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22)
Look at the food web below. The frog gets it energy from
A) crickets and pike.
B) crickets and spiders.
C) pike, crickets and spiders.
D) spiders, crickets and beetles.
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23)
An ecosystem is an area where living and non-living things affect each other.
Which of these is an example of an ecosystem?
A) desert
B) rocks
C) soil
D) weather
24)
A producer is
A) an animal.
B) a dead animal.
C) a plant.
D) the sun.
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