00:01
Depolarization of a neuron to threshold stimulates.
00:05
A, the opening of sodium channels.
00:08
B, the delayed closing of sodium channels.
00:10
C, the delayed opening of calcium channels.
00:13
D, a and c, or e, all of the above.
00:16
Okay, so i'll start by drawing out what an action potential looks like.
00:19
But when you hit threshold potential, you get an action potential.
00:25
Goes up, goes down, overshoots, and then goes back to normal.
00:29
Resting.
00:30
So if we look at what happens in each of these, we can see what's happening with the channels in the membrane.
00:37
Because the initial spike is due to the opening of the sodium channels.
00:41
So a happens, that's the immediate response.
00:45
So at threshold, the na plus channels open and na plus enters the cell...