And let's begin with the ligand gated ion channel. Now, this is basically a channel, a transmembrane protein that allows the flow of different types of ions. So sometimes we have sodium, we can have potassium, we can have chloride calcium. So basically, these ions flow across the cell membrane from a high concentration to low concentration gradient. And the opening of these channels is a result of the binding of some type of stimulatory molecule. And this stimulatory molecule is known as a ligand.