The ΔG calculation for the two-Na⁺/one-glucose symporter includes which of the following terms?
A)RT ln [glucoseᵢn]/[glucoseₒᵤt]
B)2RT ln [Na⁺ᵢn]/[Na⁺ₒᵤt]
C)2FE
D)all of the above

Question

Quizplus · Accepted Answer

The ΔG calculation for the two-Na⁺/one-glucose symporter includes all three terms: RT ln [glucoseᵢn]/[glucoseₒᵤt], 2RT ln [Na⁺ᵢn]/[Na⁺ₒᵤt], and 2FE (the electrostatic potential energy term). RT ln [glucoseᵢn]/[glucoseₒᵤt] accounts for the concentration gradient of glucose across the membrane, while 2RT ln [Na⁺ᵢn]/[Na⁺ₒᵤt] accounts for the concentration gradient of Na⁺ across the membrane. 2FE accounts for the energy required to move Na⁺ ions against their electrostatic potential. Thus, all three terms are needed to fully account for the ΔG of this symporter.

The ΔG Calculation for the Two-Na⁺/one-Glucose Symporter Includes Which of the Following