Chapter 19, Problem 81GP

& BIO Current across membrane wall of axon An axon cable that connects the input and output ends of a human nerve cell is $\text{5}**\#x00D7;{\text{10}}^{\text{-6}}$ m in radius and 0.5 m long. The thickness of the membrane surrounding the fluid in the axon is $\text{6}\times {\text{10}}^{\text{-9}}\text{m}$, its resistivity is $1.6\times {10}^7\Omega \cdot \text{m}$

, and there is a 0.070-V potential difference across the membrane. (a) Determine the current through the membrane. (b) If the current is due to sodium ions, how many of these ions leak across the membrane wall per second? (c) How does the current change if the membrane is twice as thick?