00:01
Okay, i want to answer this question, let's talk about ligand -gated ion channels, okay? this question says, lichen -gated ion channels play important goals in relaying information between neurons and synapses.
00:12
An outline of the structure of a synapse is shown in this diagram here.
00:17
The question of the following statements most accurately describes ligand -gated ion channels.
00:21
Well, as you can see here, you have vesicles in that this is a presynaptic neuron and this is a post -synaptic neuron.
00:27
Okay.
00:28
Here we have in the axon terminal, we have vesicles containing neurotransmitters.
00:34
And because of calcium influx, there is going to be exocytocase of these vesicles, and there is going to be released of the neurotransmitter to this synapse.
00:43
And then these neurotransmitters are going to bind two receptors on the membrane of the post -synaptic neuron.
00:49
Let's suppose that these receptors are ligand -gated ion channels.
00:53
It means, let's write it here, like an gated ion channels.
01:02
It means they are ion channels.
01:04
Imagine this is a cell membrane.
01:06
And here you have ion channels.
01:08
Remember that ion channels normally move ions across a cell membrane through these transporters, this protein transporters, down the concentration grades.
01:17
Okay, for example, if you have higher levels of potassium here, and lower level of potassium here, then sodium is going to, i'm sorry, this is sodium, sodium is going to move in this direction, okay? from the extracellular to the intraceous.
01:30
So, in case of ligand -gated ion channels, they are going to be ion channels, but they are going to operate when a ligand mines there.
01:40
For example, let's suppose that this ion channel is normally clothed.
01:46
But when a ligand comes and mines there, then this ion channel is going to open and it is going to allow the movement of sodium down the concentration rate.
01:57
Okay, so this is what you are.
01:58
That these ligand -gated ion channels are, they are going to respond to the binding of a ligand.
02:04
And also, remember that it does not only respond, or practically, this ligand -gated ion channels are not going to necessarily open the channels when a ligand binds, but there are, depending on the type of transporter that you have, the binding of a ligand can close the channel...