What causes depolarisation during an action potential?
Answer and explanation
Correct answer: D. Voltage-gated sodium channels open and sodium ions enter the axon
- Step 1: A stimulus above threshold opens sodium channels. Step 2. Sodium diffuses in down the electrochemical gradient, making the inside positive. Answer: Voltage-gated sodium channels open and sodium ions enter the axon. Why not the others: potassium ions leave during repolarisation; the pump does not cause depolarisation; chloride ions have no major role.
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