This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
Equilibrium potential for an ion is calculated using 
Select and explain. 
A. Gibbs Donnan equation, B. Goldman equation, C. Nernst equation, D. Henderson Hesselbach equation
C: Nernst equation
Answer: C: Nernst equation 
Explanation: Equilibrium potential for an ion is calculated by Nernst equation. the Nernst potential corre- sponding to this ratio is -94 millivolts because the loga- rithm of 35 is 1.54, and this multiplied by -61 millivolts is -94 millivolts. Therefore, if potassium ions were the only factor causing the resting potential, the resting potential inside the fiber would be equal to -94 millivolts, as shown in the figure. (REF: TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, 28)