The minimum unit of contraction of a muscle fiber is
A) a summation.
B) a tetanus.
C) a twitch.
D) a sustained contraction.
E) the smallest number of fibers in a motor unit.

Question

Quizplus · Accepted Answer

The minimum unit of contraction of a muscle fiber is a twitch, which is a brief contraction and relaxation in response to a single stimulus. A summation is the process by which multiple twitch contractions combine to produce a stronger overall contraction. A tetanus is a sustained contraction that occurs when stimuli are delivered rapidly and continuously, causing the muscle fiber to reach maximal contraction and remain contracted. A sustained contraction is a continuous contraction that is maintained at a consistent level. The smallest number of fibers in a motor unit can vary depending on the muscle, but it is typically in the range of a few dozen to a few hundred.

The Minimum Unit of Contraction of a Muscle Fiber Is