Question

Which injury would likely cause the body to permanently lose the ability to perform simple reflexes?

damage to the nerve cells in the spinal cord
a muscle tear in the leg
the death of a single neuron in the body
harm to a nerve in the skin

Answer 1

Damage to the nerve cells in the spinal cord.

Simple reflexes depend on an intact reflex arc (sensory neuron → integration in the spinal cord → motor neuron → muscle). Damage to spinal cord nerve cells disrupts the central integration and motor output and is often permanent because central nervous system neurons have very limited ability to regenerate. A muscle tear, death of a single neuron, or injury to a skin nerve are less likely to cause a permanent loss of basic reflexes.