The extrafusal fibers of a muscle spindle receive their nerve supply from which of the following?
A) primary sensory endings
B) secondary sensory endings
C) dynamic $\gamma$ motor neuron
D) static $\gamma$ motor neuron
E)$\alpha$ motor neuron

Question

Quizplus · Accepted Answer

The extrafusal fibers of a muscle spindle receive their nerve supply from γ-motor neurons, which are responsible for regulating the sensitivity of the intrafusal fibers. The γ-motor neurons are activated by α-motor neurons, which provide the motor innervation to the extrafusal fibers. Therefore, the correct choice is E, which represents the α-motor neurons.

The Extrafusal Fibers of a Muscle Spindle Receive Their Nerve γ\gammaγ

The Extrafusal Fibers of a Muscle Spindle Receive Their Nerve $\gamma$