How does myelination affect nerve impulse conduction velocity?

Nerve impulses are propagated in the form of action potentials, involving the rapid depolarisation of the nerve cell membrane from  -70mV to +30mV, before repolarisation occurs returning the membrane potential to -70mV. This cycle of depolarisation and repolarisation is propagated along the nerve cell as an electrical signal. Myelinated axons are covered in a protective, lipid rich myelin sheath produced by Schwann cells. This insulates regions of the nerve cell, so they cannot depolarise. Regions that lack myelin are called “nodes of Ranvier” and these become the only areas where action potentials can form, resulting in “jumping” of the nerve impulse from node to node. This is called saltatory conduction. Saltatory conduction results in faster nerve impulse conduction velocity, as the action potentials can “jump” along the neuron. 

TW
Answered by Thomas W. Biology tutor

7916 Views

See similar Biology A Level tutors

Related Biology A Level answers

All answers ▸

What is the role of calcium in synaptic transmission?


How do you test for monosaccharides/disaccharides?


Describe how mark-release-recapture technique could be used to estimate a population of mosquitoes.


Explain the sliding filament theory


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences