00:01
In this question, we're asked to describe how action potentials will work to transmit information between neurons, and we're asked to make sure to indicate how they are initiated, how they're propagated, and the mechanism by which that they can influence their target neurons.
00:14
So in a neuron, which i will kind of draw a pretty simplified version, we have our axon here, and then we have our neuron here, and then i'll just draw in some dendrites, right? and so in this resting membrane potential of the neuron is going to be around minus 70 milli volts, which means there's a minus 70 millavolt charge difference between the inside and outside of the cell.
00:35
When there's an incoming threshold signal that stimulates the membrane, we'll see a voltage change.
00:41
And once this voltage change reaches a certain voltage, this will trigger an action potential.
00:48
And this sort of threshold is known as the threshold potential.
00:51
What will happen is certain voltage -gated sodium channels will open in response to the slight change in voltage.
00:59
And as these sodium ions influx into the cell, it will accelerate this voltage change and cause a basically a massive change in voltage.
01:09
And the voltage will spike during a depolarization event to positive 40 milovolts or somewhere around there...