A current

Bioelectricity refers to the electric potentials and currents produced within living organisms. These bioelectric potentials are generated by various biological processes and typically range from one to a few hundred millivolts. Historically, ancient peoples were aware of bioelectricity through electric fish like the Nile catfish and electric eel.12

In modern medicine, measuring bioelectric potentials is routine for diagnostic purposes, such as monitoring the electrical activity of the heart and brain. While bioelectric currents involve the flow of ions (charged atoms or molecules), typical electric currents used for power are electron movements.13

The cell membrane plays a crucial role in bioelectricity. It acts as a semipermeable barrier, allowing certain ions to pass while blocking others. This selective permeability, particularly for ions like potassium, creates an electrical potential difference across the membrane, known as the resting potential. Nerve and muscle cells utilize these potentials for functions like transmitting signals (action potentials) and muscle contraction. Some fish have evolved specialized organs capable of generating significant electric discharges for defense or hunting.145