13. the walls of arteries include a
muscle layer.
voluntary
smooth
cardiac
skeletal

smooth

Explanation:

The walls of arteries include a  smooth muscle layer.

smooth

Explanation:

Arteries are blood vessels that guarantee the transport of blood from the heart to the different tissues of the body, thus allowing the supply of oxygen and nutrients to all cells. These vessels are quite resistant and have some characteristics that allow them to be distinguished from other blood vessels. In addition, the artery walls are composed of three layers that differentiate between themselves. One of these layers appears as a smooth muscle layer.

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