What does the smooth muscle do?

Most smooth muscle is of the single-unit variety, that is, either the whole muscle contracts or the whole muscle relaxes, but there is multiunit smooth muscle in the trachea, the large elastic arteries, and the iris of the eye. read more

Smooth muscle is a type of muscle. Smooth muscle makes up most of the muscle in the organs such as the heart. Unlike skeletal muscle smooth muscles are not under direct voluntary control. read more

Smooth muscle is fundamentally different from skeletal muscle and cardiac muscle in terms of structure, function, excitation-contraction coupling, and mechanism of contraction. Structure Smooth muscle fibers are spindle-shaped, and, like all muscle, can contract and relax. read more