The equilibrium potential of K+ ions in nerve cells is about -90 mV. The membrane potential of typical nerve cells at rest is -70 mV. Therefore
A. Increasing the permeability of a resting neuronal membrane to K+ will make the membrane potential more negative inside with respect to outside.
B. In resting neurons, there is a net diffusion of K+ into the cell.
C. changing the resting membrane potential of a neuron to -80 mV would increase K+ diffusion rate out of the cell.
D. potassium is the only permanent ion at rest.
E. there must be another permanent ion with an equilibrium potential more negative than -90 mV.
A
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