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Given an unusual cell with an intracellular fluid containing 10 mM calcium and an extracellular fluid containing 1 mM calcium. If the cell membrane is permeable only to calcium ions, what is the voltage across the membrane? Assume that the system is at equilibrium and at body temperature.

User Bob Paulin
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1 Answer

11 votes

Answer:

The correct answer is: -31 mV

Step-by-step explanation:

Given:

Intracellular fluid concentration = 10 mM

Exracellular fluid concentration = 1 mM

temperature = 237+37 = 310 k

Z = 2

F= 96500 C mol-^1

R = 8.314 J MOL-^1K-^1

Formula -

Ex = (RT/ZF) ln ([x]out/[x]in)

=
(8.314*310*2.303)/(2*96500) log 10 (1mM)/(10mM)

= -0.03075447679*1/10 log 10

= - 31 mV

User Marslo
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