MathBench > Cellular Processes

Nernst Potential

 

Taking Nernst for a test drive

 

nernst eqation

 

Well, that was a lot of work, but we finally have a way of calculating the equilibrium potential based on the concentration gradient of an ion.

typical cellLet's give this equation a run for its money. Remember the typical cell? And remember that the cell's membrane is generally only permeable to potassium (K+)? So...

 

What is the Nernst potential associated with the potassium ion?

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I think I have the answer: -90 mV

Bet you thought that was going to be harder... Let's try another one

What is the Nernst potential associated with the sodium ion?

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I think I have the answer: +72 mV