6.4.3. Biodiversity at Risk

6.4.3. Biodiversity at Risk

by LaToya Washington

Multiple Choice

The current rate of species extinction is

• slower than at any other time in this century.

• attributable to the actions of humans.

• the result of natural environmental processes

• of little consequence to Earth’s long-term survival.

Multiple Choice

According to biologists, what percentage of species have become or are expected to become extinct between 1900 and 2100?

• 1%

• 10%

• 25%

• 60%

Multiple Choice

What groups of organisms are most in danger of extinction?

• those with small populations

• those that migrate or need special habitats

• those with large populations that breed quickly

• Both those with small populations and those that migrate or need special habitats

Multiple Choice

An endangered species is

• a species in danger of extinction.

• a species growing on public land.

• an organism brought to a place where it has not lived before.

• a species that has disappeared entirely.

Multiple Choice

What percentage of extinctions are caused by habitat loss?

• 10%

• 50%

• 75%

• 100%

Multiple Choice

What is another name for exotic species?

• indigenous species

• native

• endemic species

• non-native species

Multiple Choice

Why are exotic species harmful to native species?

• Native species have no natural defense against them.

• Exotic species might compete for the same resources.

• Exotic species might carry diseases that in which the local species is susceptible.

• All of these are reasons why exotic species are harmful.

Multiple Choice

The major human causes of extinction today are

• hunting and destroying habitats.

• polluting and introducing non-native species

• Both hunting & destroying habitats AND polluting & introducing non-native species

• Neither hunting & destroying habitats AND polluting & introducing non-native species

Fill in the Blanks

Multiple Choice

Which of the following is NOT synonymous with endemic species?

• exotic species

• indigenous species

• native species

Multiple Choice

What percentage of coral reefs are threatened by human activity?

• 20%

• 40%

• 60%

• 80%

Multiple Choice

Which of the following is NOT one of the ways in which coral reefs are threatened by human activities?

• development along waterways

• creation of artificial reefs

• overharvesting of fish

• pollution

Multiple Select

Select the four reasons why coral reefs are beneficial to humans.

• tourism revenue

• sources of new chemicals

• provide millions of people with food

• source of energy

• coastal protection

Multiple Choice

Where are many critical biodiversity hotspots located?

• cities and developed areas of the world

• islands, tropical rain forests, and coastal areas

• desert and polar environments