What primarily maintains the negative resting membrane potential of approximately -70 mV in human neurons?
Answer and explanation
Correct answer: B. High resting membrane permeability to potassium ions through constitutive potassium leak channels
The resting membrane potential is generated primarily by the high resting permeability of the plasma membrane to K+ ions through non-gated potassium leak channels, allowing K+ to diffuse down its concentration gradient out of the cell until an electrical equilibrium is established near potassium's equilibrium potential (around -90 mV). The Na+/K+ pump also contributes to maintaining the concentration gradients.
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