So they function in, number one, intercellular communication. Number two, in cell nourishment. So for instance, those cells of our body which are not found in close proximity to capillaries cannot receive the food from the capillaries. And so things like glucose and amino acids are received as a result of these gap junctions. Number three, movement of the action potential. So, for instance, in very excitable cells of our body, for instance, cardiac muscle cells, cardiac muscle cells actually use gap junctions to propagate the lecture, the action potential across the entire heart.