SMOOTH MUSCLE. Small Intestine (Jejunum), Circular Muscle Layer, 250X Shows: smooth muscle fibers (cells), and elongate nuclei. Nonstriated, involuntary muscle. [Getty Images]

SMOOTH MUSCLE. Small Intestine (Jejunum), Circular Muscle Layer, 250X Shows: smooth muscle fibers (cells), and elongate nuclei. Nonstriated, involuntary muscle.

Photolibrary Ed Reschke