💀anatomy and physiology i review

Myelin sheath

Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025

Definition

The myelin sheath is a fatty layer that surrounds the axons of many nerve cells, serving as electrical insulation and increasing the speed at which nerve impulses are conducted. It is essential for the proper functioning of the nervous system by facilitating rapid signal transmission.