Thanks Oakman, that makes sense. But it also begs the question. **Does a millivolt potential translate to a microamp flow?** A quick google search shows that 1 Millivolt/Ohm converts to 1000 microamperes, The reason I'm interested is because I'm used to reading about the potentials, not the flow. And it's also been noted that the electricity we often use in everyday situations is much too powerful for any of this. So it looks like 500 microamps is in a range that makes biological sense.

A little basic electricity gives the answer. Resistance (to flow) is what constrains electrical current (electrons). Voltage is what tries to 'push' electrons (current) through a resistance. Some examples can help here...

With a very high resistance, and a very high voltage (say 10,000 volts) you only get a small current flow according to the equation, Amps= Volts/Resistance. For example to determine in a certain case: Amps = 10,000 volts / 10,000,000 ohms equals .010 amps or 10 milliamps. This can cause a bit of pain and discomfort in the body. Reduce the voltage to 100 volts with the same resistance and the current flow is .0001 amps or 100 microamps. Not dangerous, barely (if at all ) noticeable.

And so forth. To your question, "**Does a millivolt potential translate to a microamp flow?**", it can under certain conditions of resistance. So, for example, Volts = Amps x Resistance, or V = A x R. Therefore if we have .010 volts (10 millivolts) and a .01 ohm (resistance) we get Volts = .01 x .01 = .0001 or 1 microamp current.

*You can vary these three; volts, amps, resistance and get any result you want.* An extremely low current at high voltage is what allows people to touch a van de graaf generator (VDG) and have their hair stand on edge, but feel no pain, for example.

"**ELECTRIC CURRENT:** a tabletop VDG produces an electric current below 100 uA (microamperes), which is about ten times smaller than a human is able to feel. If you lick your fingertips and touch them to the terminals of a 9v radio battery, the level of current in your fingers will be much higher than that produced by a VDG machine. As far as constant currents go, a 9v battery is more dangerous than a VDG."

http://amasci.com/emotor/safe.html

In humans, the body works with electricity like this, but at a cellular level the potentials vary greatly.

https://www3.nd.edu/...of the Body.pdf

"Resting membrane potential is approximately -95 mV in skeletal muscle cells, -60 mV in smooth muscle cells, -80 to -90 mV in astroglia, and -60 to -70 mV in neurons."

http://oer2go.org/mo...1255/index.html

**Edited by Oakman, 09 November 2019 - 03:38 PM.**