So let's begin by zooming in onto our exxon hilloc, as shown in the following diagram. So this is before any stimulus is actually applied. So before we apply our stimulus, the inner portion of the cell membrane. So this is one cell membrane on this side, and this is the other cell membrane on the other side. And this is our cytoplasm of the exxon hillock. So before we apply our stimulus, our cell membrane is resting.