Observe the action potential and state the correct events that occur in Phase I and Phase II.

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Phase I is depolarization. When a stimulus greater than the threshold stimulus is applied at a point in the axon, the sodium channels open causing movement of sodium ions from the extracellular fluid to the axoplasm. Due to this, the membrane potential rises from $- 70 m V$ to $+ 30 m V$ .

Phase II is repolarization. After depolarization is over, the potassium channels open causing movement of potassium ions from the axoplasm to the extracellular fluid. Due to this, the membrane potential falls from $+ 30 m V$ to $- 70 m V$ .

Zoology - Neural Control and Coordination Question with Solution | TestHub

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