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 investigator applies a 1.0 μA peak current at 40 kHz to a cell with twice the membrane area of the cell noted in the passage, what will be the peak out-of-phase voltage?
A. 0.32 V
B. 0.16 V
C. 0.080 V
D. 0.040 V
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