An example of PNS myelinated nerve fiber is shown. (B) Illustration of transverse section of myelinated axon at the internode. (C) Light microscopy of a mouse sciatic nerve at lower magnification.

In cross section, the myelinated axon appears ... In contrast, among the myelinated nerve fibers, axons are mostly covered by myelin sheaths, and transmembrane currents can only occur at the ...