Uniporters and ion channels allow the movement of ions across cellular membranes. While both are instances of assisted transport, ion movement via an ion channel is about 104- to 105-fold quicker than molecule movement through a uniporter. What fundamental mechanistic difference contributes to this significant disparity in transport rate? The direction of travel is determined by the contribution of free energy (G).

Uniporters and ion channels allow the movement of ions across cellular membranes. While both are instances of assisted transport, ion movement via an ion channel is about 104- to 105-fold quicker than molecule movement through a uniporter. What fundamental mechanistic difference contributes to this significant disparity in transport rate? The direction of travel is determined by the contribution of free energy (G).

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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