In biological systems, the change in potential across a membrane or the current through the membrane is rarely due to the motion of isolated electrons. It is instead due to oxidization-reduction reactions that have the effect of moving ions across such boundaries. The sodium-potassium pump, comprised of a sodium-potassium adenosine triphosphatase enzyme, is responsible for the movement of potassium (K+) ions into the cell and sodium (Na+) ions out of the cell. (a) In a time interval of 1.27 x 10-8 s, three sodium ions are pumped out of a cell for every two potassium ions that enter the cell through the membrane. If the exchange of ions continues at this constant rate, what is the net current into or out of the cell (in A)? (Enter the magnitude and direction.) magnitude --Select- direction (b) If a potential difference of 35.0 mV is established across the cell membrane and the transport through the membrane can be approximated as ohmic, what is the resistance of the membrane (in N)?

In biological systems, the change in potential across a membrane or the current through the membrane is rarely due to the motion of isolated electrons. It is instead due to oxidization-reduction reactions that have the effect of moving ions across such boundaries. The sodium-potassium pump, comprised of a sodium-potassium adenosine triphosphatase enzyme, is responsible for the movement of potassium (K+) ions into the cell and sodium (Na+) ions out of the cell. (a) In a time interval of 1.27 x 10-8 s, three sodium ions are pumped out of a cell for every two potassium ions that enter the cell through the membrane. If the exchange of ions continues at this constant rate, what is the net current into or out of the cell (in A)? (Enter the magnitude and direction.) magnitude --Select- direction (b) If a potential difference of 35.0 mV is established across the cell membrane and the transport through the membrane can be approximated as ohmic, what is the resistance of the membrane (in N)?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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