Human Impact on Ecosystems Review

Humans can causes changes to the environment that are...

• positive

• negative

• positive or negative

What negative effect(s) can occur when trees are removed from an ecosystem?

• animal habitats are lost

• the amount of oxygen decreases

• soil erosion occurs more quickly

• all of these

When humans change ecosystems, they always affect the flow of...

• oxygen & carbon dioxide

• matter & energy

• water & sunlight

• predators & prey

Approximately how many people live on the planet currently?

• Between 4 and 5 billion

• Between 6 and 7 billion

• Between 7 and 8 billion

• Between 8 and 9 billion

True or False: Before buildings like homes and stores can be built, land must be cleared first.

• True

• False

All of these are examples of air pollution except...

• smog from factories

• exhaust from vehicles

• carbon dioxide from animals

• smoke from cigarettes

True or False: Light pollution isn't actually harmful because it is not physical matter.

• True

• False

All of the following are examples of natural resources except...

• iron

• paper

• aluminum

• wood

_________ is a valuable natural resource that is burned for fuel and used in products such as plastic.

• aluminum

• water

• wood

• oil

True or False: Planting two trees for every tree cut down solves the problem of deforestation.

• True

• False