Medullary and medullary nerve cells

This is what one understands by medullary nerve cells

Nerve cells are divided into non-medullary and medullary-containing cells.

• The medullary nerve cells are those nerves that run through the body without a medullary sheath.
• They consist of the cell body, the dendrites and the axon. The cell body contains the cell nucleus. The dendrites are cell extensions of the cell body, which receive excitation impulses from the neighboring cells. The axon transmits the excitation impulse to other nerves or directly to the muscle tissue.
• Schwann cells are the cells that surround the peripheral nerves. Together the Schwann cell and axon form the nerve fiber. In the unmarked nerve cells, which make up about two thirds of the nerves, this Schwann cell simply lies around the axon. The conduction of excitation is slower because the excitation impulses have to travel along the entire axon.
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This is how medullary axons are built up

• Medullary nerve cells have a myelin sheath, also called myelin sheath, Schwann sheath or neurolemm. They make up about a third of the nerve tissue.


Difference between axon and dendrite

Axons and dendrites are both parts of a nerve cell - they are used to ...

• The myelin sheath consists of the Schwann cell, which wraps itself around the axon and thereby isolates it. The myelin sheath consists of a mixture of fat and protein.
• The conduction of excitation in the medullary axons is much faster. This is due to the fact that the medullary sheath is interrupted by the so-called Ranvier rings along the length of the axon. At these constrictions, the axon lies, so to speak, without isolation. The excitation impulses now jump from ring to ring, which results in a disproportionately higher excitation conduction speed. Medullary nerve fibers are therefore found where a fast conduction speed is required.