In considering active transport by Na + -K + -ATPase at body temperature (37 o C), 3 Na+ are pumped out of the cell and 2 K + are pumped in for each ATP that is hydrolyzed to ADP + P i . Given that underyour experimental conditions, the DG for ATP hydrolysis is -10 kcal/mol, and that V is -60 mV, and that the pump maintains the internal Na + at 10mM, external Na + at 120 mM, internal K + at 120 mM and external K + at 8mM, what is the efficiency of the pump (i.e., what fraction of the energy available from ATP hydrolysis is required to drive transport at the provided levels)?

In considering active transport by Na + -K + -ATPase at body temperature (37 o C), 3 Na+ are pumped out of the cell and 2 K + are pumped in for each ATP that is hydrolyzed to ADP + P i . Given that underyour experimental conditions, the DG for ATP hydrolysis is -10 kcal/mol, and that V is -60 mV, and that the pump maintains the internal Na + at 10mM, external Na + at 120 mM, internal K + at 120 mM and external K + at 8mM, what is the efficiency of the pump (i.e., what fraction of the energy available from ATP hydrolysis is required to drive transport at the provided levels)?

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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