For example, we have different types of proteins that allow ions to pass through, and other proteins exist that allow larger molecules, such as sugars, to basically pass through. Now, what about the peripheral protein? So, peripheral proteins bind ionically via electric forces to either the integral proteins themselves or they could bind to our phospholipid bilayer. In this case, we show the peripheral protein binding to our phospholipid bilayer. And because these proteins do not actually span the entire bilayer, that means they usually do not act as transport proteins. These proteins do not span the entire membrane and function in adhesion or cell recognition, cell signaling or cell communication.