And what allows those cells, the beta cells of the pancreas, to actually sense this increase in the glucose levels in the blood are these glute two protein membranes. So these transporters are typically found in the pancreas. So the beta cells of the pancreas that release the insulin, as well as the liver, and we also find them in the vasilateral membrane of things like the kidneys, as well as our intestines. And so these membrane proteins, unlike these two, actually have a relatively large Km value of 15 nm. Now, why is that physiologically significant? Well, what that basically means is the liver cells and the pancreas cells will only begin to uptake the glucose molecules and will only begin to sense the presence of these glucose molecules if the blood levels rise.