The Nernst and Goldman equations shown are used to predict membrane potentials. Which equation is more likely to be accurate in predicting the resting membrane potential, and why?
A) The Goldman equation, because it also considers permeability of the membrane to all ions that cross it
B) The Nernst equation, because it takes into consideration the temperature of the cell
C) The Nernst equation, because it calculates permeability of the membrane to all ions that can be measured
D) The Goldman equation, because it calculates the potassium equilibrium potential
E) The Nernst equation, because it calculates the potassium equilibrium potential

Question

The Nernst and Goldman equations shown are used to predict membrane potentials.  Which equation is more likely to be accurate in predicting the resting membrane potential, and why?
A) The Goldman equation, because it also considers permeability of the membrane to all ions that cross it 
B) The Nernst equation, because it takes into consideration the temperature of the cell 
C) The Nernst equation, because it calculates permeability of the membrane to all ions that can be measured 
D) The Goldman equation, because it calculates the potassium equilibrium potential 
E) The Nernst equation, because it calculates the potassium equilibrium potential

Quizplus · Accepted Answer

The Goldman equation is more likely to be accurate in predicting the resting membrane potential because it takes into account not only the equilibrium potentials of the individual ions, but also their relative permeabilities across the membrane. This is important because the membrane is more permeable to some ions (such as potassium) than others, and their contribution to the membrane potential needs to be considered. The Nernst equation only considers the equilibrium potentials of the individual ions and does not take into account their relative permeabilities. While the temperature of the cell affects both equations, it is not the deciding factor in determining accuracy in predicting the resting membrane potential.

The Nernst and Goldman Equations Shown Are Used to Predict