(A) Illustration of myelinated nerve fiber and saltatory conduction of action potential. An example of PNS myelinated nerve fiber is shown. (B) Illustration of transverse section of myelinated ...

Amazingly, a large myelinated axon may have up to 250 to 300 turns of myelin wrapping around it. The ratio between axon diameter and that of the total nerve fiber (axon and myelin) is 0.6–0.7 ...