510 Science

Driving less or driving cars that emit less smoke helps to conserve ______.

• air

• water

• land

• fire

Planting trees helps to conserve _____.

• water

• land

• air

• fire

One way to conserve _____ is to stop companies from putting chemicals into rivers.

• water

• land

• air

• fire

The elephant is a keystone species. Elephants eat trees that grow in the savannah, allowing savannah grasses to grow. Antelopes eat the savannah grasses. What might happen in an ecosystem if elephants are removed?

• The antelope population would grow, and other species might die out.

• Other populations would remain the same because the ecosystem is balanced.

• The antelope population would decline and eventually die out.

Why is it bad for an animal to be taken to a new place where it has no predators?

• The animal might not survive in the new habitat.

• The animal might become food for another animal.

• The animal might eat all the plants or other animals and leave no food for other animals.

A natural resource that limits population growth is a(n) _____.

• endangered species

• carrying capacity

• limiting resource

The maximum number of a species an ecosystem can support for a long time is the _____.

• endangered species

• carrying capacity

• limiting resource

The _____ biome is found where there is a good amount of rainfall and warm to hot temperatures.

• temperate deciduous forest

• tropical rain forest

• desert

A _____ is a grassland where cheetahs, lions, and elephants live.

• savannah

• chaparral

• tundra

A _______ is an ecosystem that covers a large area and has certain plants, animals, and climate.

• biosphere

• community

• biome