AP Psychology Practice Test 2025 - Free AP Psychology Practice Questions and Study Guide

The myelin sheath is a crucial component of the nervous system, consisting of a layer of fatty tissue that envelops the axons of many neurons. This specialized structure serves multiple important functions. One of its primary roles is to facilitate the rapid transmission of electrical impulses along the axon, significantly enhancing the speed of neuronal communication. The myelin sheath achieves this through a process called saltatory conduction, where the electrical signal jumps between the gaps in the myelin, known as nodes of Ranvier.

Additionally, the myelin sheath provides insulation to the axons, which helps maintain the integrity of the electrical signals being transmitted. This insulation is critical for proper neural function and efficiency. Damage to the myelin sheath can lead to various neurological disorders, such as multiple sclerosis, highlighting its importance in the overall health of the nervous system.

Recognizing the myelin sheath's role as a fatty protective layer surrounding axons underscores its essential function in facilitating effective communication within the nervous system.