So we have to consider three things. Number one is there is a difference in the composition of the proteins and lipids and carbohydrates found on the two sides of the membrane. So for instance, in this particular case, we have glycolipids and glycoproteins on this side that we don't find on the other side. And likewise, we have the peripheral protein that we find on this side and don't find on the other side. Number two is we have asymmetry because of the difference in the positioning and the orientation of proteins. For instance, if we look at this transmembrane protein, this is oriented in such a way so that this side only contains the peripheral component protein and not this side.