For a typical cell that is 100 times more permeable to K* than to any other ion, use the Goldman equation to determine the potential change that would be produced by a doubling of the extracellular K+ concentration. (Use appropriate concentrations from the previous question). HINTS: Use 58 in the Goldman equation for results in mV or 0.058 for results in V. Because this problem is about change (one value relative to another), you do not need to know the permeabilities of individual ions; you only need to know that PK is 100 times higher than PNa and PCI.

For a typical cell that is 100 times more permeable to K* than to any other ion, use the Goldman equation to determine the potential change that would be produced by a doubling of the extracellular K+ concentration. (Use appropriate concentrations from the previous question). HINTS: Use 58 in the Goldman equation for results in mV or 0.058 for results in V. Because this problem is about change (one value relative to another), you do not need to know the permeabilities of individual ions; you only need to know that PK is 100 times higher than PNa and PCI.

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

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 3SQE

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If the equilibrium potential for K* is -90mV, and the charge inside the cell is -70mV, which direction will K move across the membrane assuming there is permeability (membrane leak channels) which allow it to pass?
Calculate the equilibrium membrane potentials to be expected across a membrane at 37 ∘C, with a NaCl concentration of 0.50 M on the "right side" and 0.08 M on the "left side", given the following conditions. In each case, state which side is (+) and which is (−). Membrane equally permeable to both ions.
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