Different Concentrations of Ions on Either Side of a Cell $\rarr$

question 60

Multiple Choice

Different concentrations of ions on either side of a cell membrane constitute a concentration cell, which is described by the Nernst equation given below. A cell must expend energy to maintain this concentration gradient by moving ions from one side of the membrane to the other. How much energy must be expended to transport 1 mole of sodium ions across a membrane when the sodium ion concentration is 0.10 M on one side of the membrane and 0.010 M on the other side, and the temperature is 37°C (body temperature) ?
(Given: Na⁺ + e^- $\rarr$ Na, $E _ { \mathrm { red } } ^ { 0 }$ = -2.71 V; F = 96,485 C; 1 J = 1 C V; R = 8.315 J / (mol K) )
$E = E { } ^ { \circ } - \frac { R T } { n F } \ln Q$

• A) 50 kJ
• B) 260 kJ
• C) 6.0 kJ
• D) 250 kJ
• E) 6,000 kJ

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Definitions:

Performance Measurement

The process of evaluating the efficiency and effectiveness of action, often through quantifiable metrics or benchmarks.

Output Standards

The specific quantitative measurements or outcomes expected from a job or task.

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The execution or accomplishment of specific work-related activities or responsibilities.

Relative Approach

An approach that considers context and circumstances, understanding that perceptions and solutions may vary depending on specific situations.