Becker's World of the Cell 9th Edition by Lewis Kleinsmith, Jeff Hardin, Gregory Paul Bertoni

Exercise 5

QUANTITATIVE Potassium Ion Transport. Most of the cells of your body pump potassium ions inward to maintain an internal K + concentration that is 30 to 40 times the external concentration.
(a)What is G (at 37°C)for the transport of potassium ions into a cell that maintains no membrane potential across its plasma membrane
(b)For a nerve cell with a membrane potential of 60 mV, what is G for the inward transport of potassium ions at 37°C
(c)For the nerve cell in part b, what is the maximum number of potassium ions that can be pumped inward by the hydrolysis of one ATP molecule if the ATP/ADP ratio in the cell is 5:1 and the inorganic phosphate concentration is 10 mM (Assume G ° = 7.3 kcal/mol for ATP hydrolysis.)