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Dec 2024
29m 44s

Cell Membrane Potential and Ion Balance

USMLE-Rx
About this episode

Differences in ion concentrations inside and outside a cell cause a difference in the charge of the intracellular and extracellular environments. This electrical polarization of a cell relative to its environment is referred to as cellular membrane potential. This potential serves as an energy source for a variety of cellular functions and as a way for excitable cells like muscle cells and neurons to communicate their signals. A cell controls its membrane potential by regulating the concentration of multiple ions and other charged particles. Let’s take a closer look at the biochemistry behind the cell membrane potential.

After listening to this AudioBrick, you should be able to:

  • Define equilibrium and describe the forces at work on ions across a biological membrane.
  • Discuss the importance of the Nernst equation and equilibrium potentials.
  • Describe the importance of Na-K-ATPase in relation to the resting membrane potential (Vr).
  • Describe the nonequilibrium steady-state (NESS).
  • Define and discuss the chord conductance equation.

You can also check out the original brick from our Cellular Biology collection, which is available for free.

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