But what happens if a phospholipid like this one here actually wants to rotate? So in this diagram, we see that there is a stabilized interaction that takes place between the water molecules in the aqueous environment and the polar head. And likewise, we should always note, we should also note that there are also stabilizing interactions that take place between these adjacent sections here. So the hydrocarbon portion of the adjacent hydrocarbon tails of these adjacent phospholipids. Now, when the fossil lipid tries to rotate, it actually has to physically rotate and move through that hydrocarbon core of the membrane. Hydrocarbon core of that membrane.