Biology Quiz: Keystone Species vs Indicator Species

What is a keystone species?

• A species with a huge impact on the environment

• A species that is extinct

• A species that is not important

• A species with low impact on the environment

What happened when the California sea otter was almost hunted to extinction?

• The ocean environment collapsed

• The sea urchin population decreased

• The kelp population increased

• The fish population remained the same

Why are sea otters important for the ecosystem off the coast of California?

• All of the above

• They provide a place for spawning for fish

• They eat kelp

• They provide protection for sea urchins

What is an indicator species?

• A species that is not important

• A species that tells scientists about the ecosystem

• A species that is extinct

• A species that has no impact on the environment

What can lichens tell scientists about the environment?

• The presence of air pollution

• The presence of soil pollution

• The presence of noise pollution

• The presence of water pollution

Why are some species considered more important to the health of an ecosystem?

• Because they have a huge impact on the ecosystem

• Because they are more colorful

• Because they are bigger in size

• Because they have a higher population

What does a keystone species do in an ecosystem?

• It is not important for the ecosystem

• It causes a collapse in the ecosystem

• It supports the entire ecosystem

• It has a low impact on the environment

What happened to the ecosystem off the coast of California when sea otters disappeared?

• The kelp population decreased

• The fish population increased

• The sea urchin population decreased

• The ecosystem collapsed

What are lichens sensitive to?

• Carbon dioxide and nitrogen

• Sulfur dioxide and ozone

• Methane and hydrogen

• Oxygen and helium

Why are lichens considered indicator species?

• Because they are not important for the ecosystem

• Because they are sensitive to air pollution

• Because they are colorful

• Because they are big in size