00:01
So today we'll be solving a question in biology.
00:03
As i can see from the question they've given us that, describe the ionic basis of resting membrane potential and show with evidence how changes in membrane permeability are responsible for changes in the membrane potential during the action potential in the nerve cell membrane.
00:17
Okay, so they're asking us about resting membrane potential in a nerve cell.
00:26
Resting membrane potential in the action potentials of a nerve cells called as now what we should know about resting membrane potential is that resting membrane potential is nothing but the potential that is present in resting neurons that is resting neurons okay resting neurons means neurons which are not signaling each other has voltage across the membrane and this voltage across the membrane is called as resting membrane potential difference.
01:01
Now the question is asking us is about the ionic difference in the resting membrane potentials of neuron.
01:07
Now what we should notice that the resting membrane potential itself is created by two factors.
01:14
One is the concentration of gradients.
01:18
Okay? concentration of gradient and the other factor that is responsible for the resting membrane potential is the permeability of ion.
01:29
Of ions.
01:32
So concentration of gradients and permeability of ions are the most important factors for a cemetery potential and here the ions are nothing but cateons and anions and cations include potassium and sodium anions include chlorine and proteins and amino acids together which we call as organic so these are the ions generally present across the surface of neuron.
02:06
Now what we should notice that the cell memory is able to potassium then sodium.
02:12
So that is going to create the resting potential difference that we have to see later.
02:18
Now for a quick glance, we can say that since potassium concentration is higher in cell, okay? k concentration is always high in cell, okay? higher in cell.
02:31
Since it's being high in the cell as per natural process, the potassium will be moving from the higher concentration which is inside the cell to the lower concentration.
02:43
Okay, lower concentration means outside the cell, therefore move down the concentration gradient via channels, therefore creating a separation of charge because the potassium ions are moving from a higher concentration which is inside the cell to a lower concentration which is outside the cell therefore creating an separation of charge okay because of this the actual resting potential actual resting potential value is closed to a equilibrium equilibrium potential of potassium okay because the concentration of potassium being higher in the cell therefore in the higher concentration the actual value of the resting potential across the cell membrane in the neuron is equal to the equilibrium potential of potassium.
03:42
Now, since ions being very small molecules, they are actually impermeable to the cell membrane.
03:52
Ions are impermeable or moreover we can say the cell membrane is impermeable to substances like ions.
04:00
So there are special channels in the cell membrane called as hydrophilic channels...