Which of the following defines a motor unit?
A) a single motor neuron and all of the muscle fibers it innervates
B) a single muscle fiber and all of the motor neurons that innervate it
C) all of the motor neurons and muscle fibers necessary to produce a single movement
D) a group of motor neurons and muscle fibers that activate together

Question

Quizplus · Accepted Answer

A motor unit consists of a single motor neuron and all of the muscle fibers it innervates. When the motor neuron fires an action potential, all of the muscle fibers it innervates contract together.

Which of the Following Defines a Motor Unit