Question

What is saltatory conduction? How is it different from continuous conduction and how does it affect conduction velocity? What else may affect the velocity of conduction?

Answer 1

Saltatory conduction: When the action potential propagates through myelinated axons between nodes of Ranvier. That is called Saltatory Conduction.

The difference between Saltatory and Continuous conduction: In the case of Saltatory conduction the action potential propagates through myelinated axons whereas in continuous conduction it propagates through the unmyelinated axon.

As the propagation of action potential happens in myelinated axons which contains myelinated sheaths, within that sheaths are present uninsulated spaces which are called nodes of Ranvier. As impulse travels via jumping from one node of Ranvier to others rather than covering entire length of the axon. Hence, the Saltatory conduction is faster as compared to Continous conduction.

How the velocity of conduction is affected: The velocity of conduction is affected by the following factors:

1. Use of Na+ and K+ channels. As Saltatory Conduction uses the minimum number of K+ and Na+ channels the propagation of action potential is faster as compared to Continuous Conduction which uses more of these channels.
2. Use of Energy: Velocity of conduction is affected by the use of energy. If the use of energy is less, then conduction is more efficient as resting membrane potential is maintained.