What Is Myelin

question 10

Multiple Choice

What is myelin?

• A) a three-part brain component that includes the sending end of one neuron, the receiving end of another, and the space in between
• B) a fatty substance that forms a sheath around axons
• C) the fluid in the space between two neurons
• D) a neurotransmitter made of dopamine

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Definitions:

Flowing-Water Ecosystem

A river or stream ecosystem.

River

A natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake, or another river.

Freshwater Wetlands

Areas of land covered by fresh water for part of or all of the year, characterized by distinct plant and animal communities.

Marshes

Wetland areas often inundated with water, characterized by soft, waterlogged soil and aquatic plants.