What is the Difference Between Myelinated and Unmyelinated Axons?

The main differences between myelinated and unmyelinated axons are related to their structure, conduction velocity, and function. Here is a comparison of the two types of axons:

Myelinated Axons:

Have a myelin sheath, which is a layer of myelin that serves as an outer covering of the axons.
The myelin sheath is produced by oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system.
The myelin sheath works like cable insulators, speeding up the electrical signal transmission along the axon.
Myelinated axons transmit action potentials faster than unmyelinated axons.
The axon length is typically shorter than that of unmyelinated axons.
The thickness of myelinated axons is greater than that of unmyelinated axons.
Myelinated axons produce collateral nerve fibers, while unmyelinated fibers do not.

Unmyelinated Axons:

Lack a myelin sheath.
Available for flicker and thermal detection.
Have a slower conduction velocity compared to myelinated axons.
The axon length is typically longer than that of myelinated axons.
The thickness of unmyelinated axons is less than that of myelinated axons.
Unmyelinated axons do not produce collateral nerve fibers.

Both myelinated and unmyelinated axons are part of the nervous system and conduct nerve impulses as electrical signals. The differences in structure and conduction velocity between these two types of axons result in myelinated axons being better at conducting nerve impulses.

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What is the Difference Between Myelinated and Unmyelinated Axons?

Comparative Table: Myelinated vs Unmyelinated Axons

Here is a table comparing the differences between myelinated and unmyelinated axons:

Feature	Myelinated Axons	Unmyelinated Axons
Myelin Sheath	Present; a layer of myelin serves as the outer covering of the axons in these fibers.	Absence of myelin sheath around the axon.
Color	White; the myelin sheath is a fatty substance that acts as insulation to protect the nerve fibers.	Grey.
Thickness	Thicker than unmyelinated axons.	Thinner than myelinated axons.
Nodes of Ranvier	Present; these are gaps between the myelin sheaths that help in the conduction of nerve impulses.	Absent.
Collateral Fibers	Produce collateral nerve fibers.	Do not produce collateral nerve fibers.
Speed of Nerve Impulse Conduction	Faster due to the presence of the myelin sheath.	Slower due to the absence of the myelin sheath.

Both myelinated and unmyelinated axons are part of the nervous system and conduct nerve impulses as electrical signals.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.