In Some Parts of the United States, Pathways for Wildlife

question 54

Multiple Choice

In some parts of the United States, pathways for wildlife are built over or under highways to allow animals to cross safely. This is an example of

• A) a dispersal limitation.
• B) a habitat corridor.
• C) an ecological envelope.
• D) an ecological passage.

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Definitions:

Ras Proteins

A group of small G proteins, named by their discovery in rat sarcoma cancer cells; important in many signaling pathways.

Cyclic Adenosine

A cyclic form of adenosine monophosphate important in intracellular signaling processes.

Serotonin

A neurotransmitter of the biogenic amine group; important in mood and helps regulate the sleep–wake cycle.

Dopamine

A neurotransmitter of the biogenic amine group; important in motor function.