Neurophysiologists are studying recordings of the membrane potential from a giant squid axon. A portion of their recordings is shown on the slide below. The membrane is most permeable to potassium ions at which of the following points?

Question

Neurophysiologists are studying recordings of the membrane potential from a giant squid axon. A portion of their recordings is shown on the slide below.  The membrane is most permeable to potassium ions at which of the following points?

Quizplus · Accepted Answer

11ec160b_3cd3_6126_9249_853ddb2997c7_MD0001_00 The graph depicts the potential voltage changes across a cell membrane; these changes (depolarization, repolarization, hyperpolarization, and resting potential) are collectively known as the action potential. The action potential occurs due to changes in the membrane permeability to Na⁺ and K⁺ ions. The membrane potential of an excitable cell (eg, nerve and muscle) cycles through the following stages: Educational objective: The action potential results from changes in the membrane permeability to K⁺ and Na⁺ ions. Depolarization results from massive influx of Na⁺ through voltage-gated Na⁺ channels. Repolarization occurs due to closure of voltage-gated Na⁺ channels and opening of voltage-gated K⁺ channels. K⁺ ion permeance is highest during the repolarization phase of the action potential.

Neurophysiologists Are Studying Recordings of the Membrane Potential from a Giant