So, anterioral proteins extend throughout the entire bilayer membrane. And their usual function, because they extend through the entire membrane, is to transport things from the inner portion to the outer portion of our cell. So basically to the outside, or vice versa, from the outside to our inside. 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.