These Physl 341 notes are modified from Bio 303 lecture notes , originally prepared by Dr. Paul Patton. Problems arise when an electrical conductor is submerged in salt water, even if the conductor is insulated. Problem first faced in 19th century in relation to development of transatlantic telegraph cables. Showed electrical currents not suitable for signaling over distances spanned by axons.
Wires are passive.
AP conduction is active. Without myelin, AP will move slowly along denuded areas of axon because of increased capacitance, in some cases AP will fail entirely because of sparsity of channels.