The Nernst equation can be used to calculate the membrane po

The Nernst equation can be used to calculate the membrane potential based on the ratio of the outer and inner ion concentration. In a resting cell, membrane potential is calculated taking only K^+ ions into account. What is V when C_o = 15 mM and C_i = 106 mM? a. -52.7 mV b. -5.3 mV c. 5.3 mV d. 52.7 mV e. 438.1 mV

Solution

We know V= RT/ZF log[K]o /[K]i

[K]o = outside concentration of K+

[K]i = inner concentration of K+

Now,

RT/ZF value is 61.5 mV,

Therefore RT/ZF Log [15]/[106]

Or, 61.5× log 15/106

Or, 61.5 × - 0.85

Or, - 52.5

There V = - 52.5 mV

Negative value mean outside of the cell is positive.