What advantage does having a myelin sheath produced by Schwann cells have for the impulse?

Spontaneous repair of peripheral nerves is made possible by Schwann cells, which surround the nerve fibers with an insulating layer, myelin. This fatty layer protects the nerves and increases the speed of transmission of nerve impulses.

Explanation:

Schwann cells are small elements that are created in order to form a layer around the axon of the nerves of the peripheral system. These cells surround the axon by an extensive layer of myelin that is discontinued by the presence of Ranvier's node. Myelin is a single cell organelle, a modified extension of the plasma membrane of the Schwann cell in the peripheral nerve. Its elaboration depends on the regulated expression of a set of genes in the myelinating glia, for which the Schwann cells require axonal contact, as well as to maintain the expression of these genes. Myelin acts as an electrical insulator that facilitates the conduction of the nerve impulse, it helps when the axons must regenerate, that is, when there is some injury or disease that prevents cell transmission. The goal is to help the nerve regenerate and grow again to reach the target tissues. Once the nerve is repaired, the cell regains its ability to produce myelin to cover the nerve with the insulating layer and allow the correct transmission of nerve impulses.

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