Answered: What is a myelin sheath? How is it…

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

See similar textbooks

Related questions

Question

What is a myelin sheath? How is it formed in the CNS? In
the PNS?

Expert Solution

Step 1

The nervous system's myelin sheath serves a variety of purposes. It plays an important role in protecting the nerve from other electrical signals, and the time required for a nerve to cross an axon is reduced.

Step 2

Myelin is a sheath-like insulating substance that exists around nerves, even those in the brain and spinal cord. Protein and fatty compounds make up this material. Electrical signals can travel rapidly and easily along with nerve cells due to the myelin sheath.
Each myelin sheath is formed from the concentric covering of an oligodendrocyte in the CNS. Axons bear electrical impulses from one nerve cell body to another in the CNS. The Schwann cell (a limb-like projection from the cell body) wraps around the axon in a concentric pattern to form each myelin sheath in the PNS. Axons in the PNS bear impulses from sensory organs like the skin to muscles and glands.