(b) The actual resting membrane potential of the cell is not only dependent on the individual components calculated above, but also relates to the overall permeability of the cell membrane to each of the ion types. It turns out that the majority of the total resting membrane potential for a cell (Atotal) is derived from the movement of K+ ions, accounting for ~90% of the total potential. In contrast the contribution from Na+ is ~ 1%, Ca2+ is ~1%, and for Cl- is ~8%. Given these values, and the individual A values calculated in part (a), estimate the overall membrane resting potential.

(b) The actual resting membrane potential of the cell is not only dependent on the individual components calculated above, but also relates to the overall permeability of the cell membrane to each of the ion types. It turns out that the majority of the total resting membrane potential for a cell (Atotal) is derived from the movement of K+ ions, accounting for ~90% of the total potential. In contrast the contribution from Na+ is ~ 1%, Ca2+ is ~1%, and for Cl- is ~8%. Given these values, and the individual A values calculated in part (a), estimate the overall membrane resting potential.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter3: The Plasma Membrane And Membrane Potential

Section: Chapter Questions

Problem 2SQE: One of the important uses of the Nernst equation is in describing the flow of ions across plasma...

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