Chapter 4 Review
Question 1
Which describes a balanced ecosystem?
• a. There is enough food for people to
exist.
• b. One type of animal and plant depend
on each other.
• c. No animal or plant drives out other
animals or plants.
• d. Humans create shelter and food for
animals and plants.
Answer…
• c. No animal or plant drives out
other animals or plants.
Question 2
A meadow has too many rabbits. What
would help balance this ecosystem?
• a. more rain that grass needs
• b. more foxes that eat rabbits
• c. fewer foxes that eat rabbits
• d. more grass for rabbits to eat
Answer…
• b. more foxes that eat rabbits
Question 3
How do grass and rabbits’ interactions help
balance their ecosystem?
• a. Rabbits make homes in grass.
• b. Grass and rabbits both need oxygen.
• c. Grass makes oxygen, and animals use
it.
• d. Grass depends on rabbits to protect it.
Answer…
• c. Grass makes oxygen, and
animals use it.
Question 4
What impact does a parasite have in an
ecosystem?
• a. helps the entire ecosystem
• b. hurts one organism and helps another
• c. helps both the host organism and
parasite
• d. hurts both the host organism and
parasite
Answer…
• b. hurts one organism and
helps another
Question 5
How would an ecosystem change if the rabbits that
were the main prey for foxes became sick and
died?
• a. The foxes would find new prey.
• b. The number of foxes would increase.
• c. The number of foxes would decrease.
• d. The foxes and rabbits would compete for
food.
Answer…
• c. The number of foxes
would decrease.
Question 6
Which would cause an ecosystem to change
quickly?
• a. an earthquake
• b. a lake drying up
• c. a climate change
• d. a lake becoming a marsh
Answer…
• a. an earthquake
Question 7
What might be the effect on an ecosystem of
a climate change from rainy to dry?
• a. no change
• b. a change from plants to animals
• c. a change from a forest to marsh
• d. a change in kinds of plants and animals
Answer…
• d. a change in kinds of plants
and animals
Question 8
What could scientists tell from a fish fossil
found in a desert?
• a. That fish is now extinct.
• b. Fish once had legs to travel.
• c. Fish once lived in dry places.
• d. The desert was once a sea or lake.
Answer…
• d. The desert was once a sea
or lake.
Question 9
What might be a reason an animal becomes
extinct?
• a. It is a predator.
• b. It produces oxygen.
• c. Its habitat is destroyed.
• d. It adapts to its environment.
Answer…
• c. Its habitat is destroyed.
Question 10
What is one way people can disturb the
balance of ecosystems?
• a. breathing air
• b. planting trees
• c. riding bicycles
• d. building houses
Answer…
• d. building houses
Question 11
How are a hawk and an owl able to
succeed, even though they compete for
food?
• a. The hawk eats the owl.
• b. The owl changes its diet.
• c. One animal moves to a different
habitat.
• d. One hunts at night, and the other hunts
during daytime.
Answer…
• d. One hunts at night, and the
other hunts during daytime.
Question 12
Why did the United States establish national
parks?
• a. to make money for the national government
• b. to provide Americans with great vacation
spots
• c. to preserve nature’s beauty and habitats of
plants and animals
• d. to give Americans a chance to see things
they’ve never seen before.
Answer…
• c. to preserve nature’s beauty
and habitats of plants and
animals
Question 13
How can damage from strip mines be
repaired?
• a. Erosion can fill the hole.
• b. Mining companies can replace the soil.
• c. Rain can wash the rock away into
rivers.
• d. Mining companies can go mine in
another place.
Answer…
• b. Mining companies can replace
the soil.