Question

What are two primary factors that can alter conduction velocity of an action potential down an axon and why do they alter the velocity?

Answer 1

Two primary factors are:

1. Temperature-

Increase in temperature causes an increase in rate of diffusion of ions across the membrane.

2. Cross sectional area of the axon-

Increased diameter of axon , will result in a faster impulse propagation down the axon, due to decrease in resistance within the lumen.

3. Increase mylenation also increases conduction velocity.

As an action potential travels down an axon there is a change in polarity across the membrane of the axon. Resulting in alteration in velocity.

In response to a signal from another neuron, sodium and potassium gated ion channels open and close as the membrane reaches its threshold potential.