Match the term with its definition.
2. Vulnerable species
3. Threatened species
4. Extirpated species
5. Endangered species
6. Extinct species
7. Keystone species
a. Any species that is at risk because of declining numbers.
b. A species that is close to extinction in all parts of a country or in a significantly large area.
c. Any species that no longer exists in one part of a country, but can be found in others.
d. The variety of life in a particular ecosystem.
e. A species that has strong interactions with other species and affects their health and survival.
f. A species that is not found anywhere.
g. Any species that is likely to become endangered if the factors that make it vulnerable are not reversed.