system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Where does the body get the electricity it uses in the brain and nervous system?
gpt
The energy you get from food is spent (in the form of ATP) to push sodium and potassium ions through pumps in the membrane of your nerve cells. Since the ions have an electric charge, they cause a voltage across the cell when the concentration is different between the inside and outside. When a nerve is activated, the flood gates in the cell membrane open and let the ions move back, which sends the electric current down the nerve. It then takes some time (a few milliseconds) to recharge the nerve, moving the ions back into place before it can fire again.