Myeliinipeitetyillä

Myeliinipeitetyillä refers to structures or tissues that are covered or insulated by myelin. Myelin is a fatty, insulating substance that is produced by glial cells in the nervous system. In the peripheral nervous system, Schwann cells produce myelin, while in the central nervous system, oligodendrocytes are responsible. This myelin sheath wraps around nerve fibers, also known as axons, in a segmented manner.

The primary function of the myelin sheath is to speed up the transmission of nerve impulses. The myelin acts as an electrical insulator, preventing the leakage of electrical signals from the axon. This insulation allows the action potential, the electrical signal of a neuron, to "jump" from one unmyelinated gap in the myelin sheath, called a Node of Ranvier, to the next. This process is known as saltatory conduction, and it significantly increases the speed at which signals travel along the axon.

Conditions that affect the myelin sheath, such as multiple sclerosis, lead to the demyelination or loss of this insulating layer. This damage disrupts or slows down nerve impulse transmission, resulting in a range of neurological symptoms. Therefore, tissues and structures that are myeliinipeitetyillä are crucial for efficient and rapid communication within the nervous system.