Predict/Calculate BIO Current Through a Cell Membrane A typical cell membrane is 8.0 nm thick and has an electrical resistivity of 1.3 × 107 Ω.m (a) If the potential difference between the inner and outer surfaces of a cell membrane is 75 mV, how much current flows through a square area of membrane 1.0 µm on a side? (b) Suppose the thickness of the membrane is doubled, but the resistivity and potential difference remain the same. Does the current increase or decrease? By what factor?
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