The membrane separating compartments A and B of the following chamber is permeab
ID: 48224 • Letter: T
Question
The membrane separating compartments A and B of the following chamber is permeable only to Clions (gCl = 5). The initial concentrations of KCl in compartments A and B, before diffusion has occurred, are presented below. Use this information to answer questions 13-18. Note: Whenever necessary, consider compartment A as the ICF and compartment B as the ECF.
A: KCl = 10 mM B: KCl = 145 mM
13) After equilibrium, the measurable concentration of KCl in compartment A will be:
A) 5 mM.
B) 10 mM.
C) 77.5 mM.
D) 145 mM.
14) After equilibrium, the measurable concentration of KCl in compartment B will be: A) 10 mM.
B) 72.5 mM.
C) 77.5 mM.
D) 145 mM
15) At equilibrium, compartment A will be _____mV (include polarity) compared to a reference of 0 mV. Consider compartment B as the outside.
A) 70 mV
B) -70 mV
C) 90 mV
D) -90 mV
16) Increasing the concentration of [Cl- ] in compartment B from 145 mM to 180 mM will ______________. Consider compartment B as the outside.
A) reduce the absolute value of ECl.
B) reduce the absolute value of EK.
C) increase the absolute value of ECl.
D) not change the absolute value of ECl.
17) At equilibrium, the flux of Clfrom compartment A to compartment B will be ______ the flux of Clfrom compartment B to compartment A.
A) equal to
B) less than
C) more than
18) If the conductance for Cl- (gCl) is increased from 5 to 10, the equilibrium potential for Cl- will:
A) become larger.
B) become smaller.
C) not change.
Explanation / Answer
13. D) 145 mM
After equilibrium the measurable concentration of KCl in compartment A will be the initial concentration of KCl in compartment B.
14. A) 10 mM.
After equilibrium the measurable concentration of KCl in compartment B will be the initial concentration of KCl in compartment A.
15. B) -70 mV
At equilibrium inner side of the membrane will have negative polarity.
16. B) reduce the absolute value of EK
Increase in the concentration of calcium ions will reduce the concentration of potassium ions.
17. A) equal to
At equilibrium there will be no nett change in the concentration of ions across the membrane.