And then we have the polar interactions, we have hydrogen bonds between the water molecules in the aqueous environment and these polar heads, and also the electrostatic interactions between these nearby polar molecules which are lined right next to one another. So we see that therefore, the tails spontaneously aggregate in the interior of the membrane because this is what creates a stabilizing system. So it allows those trap water molecules to be released and how these water molecules can form stabilizing hydrogen bonds with these polar heads. In addition, we have the lung dispersion forces that exist between the adjacent tails on the interior portion of the structure. We have the electrical and hydrogen bonds that exist between these adjacent heads. And we also have these hydrogen bonds between water molecules and these heads.