The mix of cellular pumps, channels, transporters, and isoenzymes is genetically inherited. However, the environment has the ability to impact the cellular pumps, channels, transporters, and isoenzymes to some degree. Cellular pumps, channels, transporters and isoenzymes help control cellular pH and vice versa. Therefore possibly the pH in the nervous system is more variable than previously believed. If so, that could explain some of the changes we see in the nervous system.