Myelin Sheath

The myelin sheath is a specialized structure that forms an insulating layer around the axons of neurons. It is composed of lipids and proteins, and its primary function is to increase the speed and efficiency of nerve impulse conduction.

Structure of Myelin Sheath

The myelin sheath is formed by Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system. These cells wrap around the axon, creating multiple layers of membrane that form the myelin sheath.

Function of Myelin Sheath

The main function of the myelin sheath is to insulate the axon, allowing for rapid conduction of nerve impulses. This is achieved through a process called saltatory conduction, where the nerve impulse jumps from one node of Ranvier to the next, rather than traveling along the entire length of the axon. This significantly increases the speed of nerve impulse transmission.

Related Disorders

Damage to the myelin sheath can lead to a range of neurological disorders, such as multiple sclerosis, where the immune system attacks the myelin sheath, leading to impaired nerve function.

Study Guide

1. Describe the structure of the myelin sheath and the cells responsible for its formation.
2. Explain the function of the myelin sheath in increasing the speed of nerve impulse conduction.
3. Discuss the process of saltatory conduction and its role in nerve impulse transmission.
4. Explore the impact of damage to the myelin sheath on neurological function, citing examples of related disorders.