Ultimately,the Base Level of a Stream Valley Can Be No

question 1

Multiple Choice

Ultimately,the base level of a stream valley can be no lower than ________.

• A)the average elevation of the continent on which it is found
• B)sea level
• C)the average elevation of the local catchment
• D)the maximum elevation of the local catchment

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Definitions:

Endemic Species

Species that are native to and can be found only within a specific geographic area.

Keystone Species

A species that plays a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem.

Pioneer Species

The first species to colonize previously disrupted or damaged ecosystems, starting a chain of ecological succession that ultimately leads to a more biodiverse steady-state ecosystem.

Herbivory

The eating of plants by animals, a biological interaction essential for energy transfer in many ecosystems.