And let's take a look at this diagram. So, in this section, we basically have the action of that acetylcholine receptor. So as it is opened up as a result of the binding of that ligand, the acetylcholine, it causes an increase in that voltage value. And eventually, if that voltage reaches the threshold voltage, it causes the rapid opening of the voltage gated sodium ion channels. At the same time, it causes a slow opening of those potassium voltage gated ion channels. And so, because we have the rapid opening of these voltage gated sodium ion channels, these sodium ions move into the cell and that makes the inside positive with respect to the outside.