How would an ecosystem change if the rabbits that were the main prey for foxes becamse sick and died?
The number of foxes would decrease.
100
What impact does a parasite have in an ecosystem?
It hurts one organism and helps another
100
Why do chipmunks in the Great Smoky Mountains survive?
Their needs are met in that environment.
100
Explain the relationship between parasites and hosts.
Parasites live on another organism called a host. The parasite uses the host as a source of food and harms the host.
100
Which describes a balanced ecosystem?
No animal or plant drives out the other animals or plants.
200
What might be the effect on an ecosystem of a climate change from rainy to dry?
a change in kinds of plants and animals
200
What might happen to a parasite if its host dies?
The parasite would either die or it would have to find a new home.
200
How do the organisms' interactions in a medow ecosystem help balance that ecosystem?
Grass makes oxygen, and animals use it.
200
How could a flood affect an entire ecosystem?
A flood can completely change an ecosystem quickly. The water might make the grass die, which would mean the animals that eat grass would move to another place or die, and the animals that prey on those animals would alsio move or die.
200
What do the illustration on pages 118 nad 119 show?
Succession
300
A meadow has too many rabbits. What would help balance this ecosystem?
more foxes that eat rabbits
300
How are a hawk and an owl able to succeed, even though they compete for food?
One hunts at night, and the other hunts during daytime.
300
What is one way people can disturb the balance of ecosystems?
building houses
300
Suppose an ant colony lives on a tree. What is the effect of chopping down the tree on the ants?
Some might die. The others would have to find a new home.
300
Why did the United States establish national parks?
to preserve nature's beauty and habitats of plants and animals
400
What might be the effect on an ecosystem of a climate change from rainy to dry?
a change in kinds of plants and animals
400
What might be a reason an animal becomes extinct?
Its habitat is destroyed.
400
How can damage from strip mines be repaired?
Mining companies can replace the soil.
400
What are some things people have done to protect the environment?
Laws have been passed to protect animals and the land. People reduce, reuse, and recycle more.
400
Name two processes that change the environment over a long period of time.
Succession and changes in climate
500
What could scientists tell from a fish fossil found in a dessert?
The desert was once a sea or lake.
500
What would cause an ecosystem to change quickly?
an earthquake
500
What human activities damage the environment?
People cut down forests, build houses, kill too many of a species, use pesticides, or bring animals from other habitats into a new habitat.
500
What is succession?
Succession is the gradual change from one community of organisms to another.
500
When is a species classified as threatened?
When the species' population has been reduced so much that they are in danger of becoming extinct.