And this cell as a whole must be able to actually use the ATP and pump these in the proper directionality to basically establish that electrochemical gradient. And so we see that asymmetry is very important to the functionality of the cell membrane. Now, when we synthesize these proteins in the ribosomes of our cell, these proteins as well as lipids actually are placed into the membrane in an asymmetric fashion. So we essentially place these proteins asymmetrically. And so we create this asymmetry in the membrane as a result of the difference in the composition and the positioning and orientation of the proteins. But the question is, how is this asymmetry?