Problem 4 (30 points) Assume you know the following initial ion concentrations and charges: Intracellular Extracellular...

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Problem 4 (30 points) Assume you know the following initial ion concentrations and charges: Intracellular Extracellular Na* Ch Proteins(-) separately. 100 mM 20 mM 80 mm, 80 mEq Na Ch Proteins(-) 100 mM 100 mM 0 mm, 0 mEq A) (10 points) Describe qualitatively in your own words how Na+ and Chions will flow across membranes to reach the Gibbs-Donnan equilibrium while maintaining bulk electroneutrality. When/why will the net flow of ions across the membranes will be zero? B) (5 points + 5 bonus points) Compute the the intracellular and extracellular concentrations of sodium ions and chloride ions after the Gibbs-Donnan Equilibrium is reached (5 points if you can provide an estimate, 5 bonus points if you can calculate the exact numbers). Provide the way how you calculated the exact values. Fill in the blanks in the following table with those values or the estimated values if you couldn't compute the exact values. Intracellular mM mM 80 mm, 80 mEq Extracellular mM mM 0 mm, 0 mEq C) (5 points) What is the Nernst potential for sodium and chloride given the final concentrations after the Gibbs-Donnan equilibrium is reached? (you can use your estimated values if you couldn't calculate the exact values). You can assume RT/F = 27.7mV. D) (5 points) Will the cell shrink or swell while reaching the Gibbs-Donnan Equilibrium? Why? E) (5 points) Compute the osmotic pressure (in atm) that will lead to swelling or shrinking. You can assume that RT = 25.4 l-atm mol Problem 4 (30 points) Assume you know the following initial ion concentrations and charges: Intracellular Extracellular Na* Ch Proteins(-) separately. 100 mM 20 mM 80 mm, 80 mEq Na Ch Proteins(-) 100 mM 100 mM 0 mm, 0 mEq A) (10 points) Describe qualitatively in your own words how Na+ and Chions will flow across membranes to reach the Gibbs-Donnan equilibrium while maintaining bulk electroneutrality. When/why will the net flow of ions across the membranes will be zero? B) (5 points + 5 bonus points) Compute the the intracellular and extracellular concentrations of sodium ions and chloride ions after the Gibbs-Donnan Equilibrium is reached (5 points if you can provide an estimate, 5 bonus points if you can calculate the exact numbers). Provide the way how you calculated the exact values. Fill in the blanks in the following table with those values or the estimated values if you couldn't compute the exact values. Intracellular mM mM 80 mm, 80 mEq Extracellular mM mM 0 mm, 0 mEq C) (5 points) What is the Nernst potential for sodium and chloride given the final concentrations after the Gibbs-Donnan equilibrium is reached? (you can use your estimated values if you couldn't calculate the exact values). You can assume RT/F = 27.7mV. D) (5 points) Will the cell shrink or swell while reaching the Gibbs-Donnan Equilibrium? Why? E) (5 points) Compute the osmotic pressure (in atm) that will lead to swelling or shrinking. You can assume that RT = 25.4 l-atm mol

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A The net flow of ions across the membrane will be zero when the GibbsDonnan equilibrium is reached ... View the full answer