The Middle Layer of the Wall of an Artery or Vein

question 50

Multiple Choice

The middle layer of the wall of an artery or vein is made up of

• A) valves.
• B) skeletal muscle.
• C) smooth muscle.
• D) endothelium.
• E) simple squamous epithelial cells.

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Definitions:

Depression

A geological formation resulting from the sinking of the Earth's surface, forming a bowl-like or flat area lower than the surrounding ground.

Valley

An elongated lowland between ranges of mountains or hills, often having a river or stream running along the bottom.

Ridge

On a weather map, an elongated area of high atmospheric pressure.

Valley Glacier

A glacier that flows down a valley and tends to be narrow; synonym: alpine glacier.