Use the dropdown lists to complete the statement: During phase 3 of the action potential,
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are open and
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is/are diffusing
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the cell.
During phase 3 of the action potential,
potassium channels are open and potassium ions are diffusing out of the cell.
During phase 3 of the action potential, voltage-gated potassium channels are open and potassium ions (K+) are diffusing out of the cell.
During phase 3 of the action potential, the voltage-gated potassium channels are open, and potassium ions (K+) are diffusing out of the cell.
To arrive at this answer, let's break down the steps:
1. What happens during phase 3 of the action potential?
Phase 3 of the action potential is known as the repolarization phase. It occurs after the rapid depolarization in phase 0 and the plateau phase of phase 2. During phase 3, the cell returns to its resting potential as the membrane potential becomes more negative again.
2. What channels are involved during phase 3?
During phase 3, the voltage-gated potassium channels (K+) are primarily involved. These channels are selective to potassium ions and can open or close in response to changes in membrane voltage.
3. What ions are diffusing?
Since the voltage-gated potassium channels are open during phase 3, potassium ions (K+) are diffusing out of the cell. This efflux of positively charged potassium ions contributes to the repolarization of the cell, leading to the restoration of the resting membrane potential.
So, to complete the statement:
During phase 3 of the action potential, the voltage-gated potassium channels are open, and potassium ions (K+) are diffusing out of the cell.