Cell Membrane Resistance
The capacitance of biological membranes is about 1.0 μF per cm2 of membrane area, so investigators can determine the surface area of a cell membrane by using intracellular electrodes to measure the membrane’s capacitive reactance. An investigator applies a 1.0 μA peak current at 40 kHz to a cell and measures the peak out-of-phase voltage—that is, the component of the voltage due to the capacitive reactance of the cell membrane—to be 0.16 V.
If the capacitance of a cell membrane is measured to be 6.0 × 10–11 F, what is the area?
A. 6.0 × 10–13 m2
B. 6.0 × 10–11 m2
C. 6.0 × 10–9 m2
D. 6.0 × 10–7 m2
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