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What are K⁺ leak channels? How do they contribute to the membrane potential = 0? What does this mean? What happens when the ion channels open? What other pump contributes to the resting membrane potential and helps with keeping the inside of the cell more negative than the outside?

User Zimkies
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Final answer:

K⁺ leak channels play a role in maintaining the resting membrane potential by allowing the slow movement of potassium ions out of the cell, creating a negative charge inside. The Na⁺/K⁺ pump also helps maintain the resting membrane potential by actively transporting ions across the membrane. The primary topic is the role of K⁺ leak channels and the Na⁺/K⁺ pump in the resting membrane potential.

Step-by-step explanation:

Leakage channels play a role in maintaining the resting membrane potential of a cell by allowing the slow movement of ions across the membrane. K⁺ leak channels specifically allow potassium ions to move out of the cell, while Na⁺ leak channels allow sodium ions to move into the cell. This movement of ions helps to balance out the charge across the membrane.

At rest, the membrane potential is approximately 0 mV because the opening of K⁺ leak channels allows K⁺ ions to move out of the cell, taking a positive charge with them. This leaves behind a negative charge inside the cell, creating a balance of charges across the membrane.

The Na⁺/K⁺ pump is another pump that contributes to the resting membrane potential. This pump actively transports three Na⁺ ions out of the cell for every two K⁺ ions it transports into the cell. This helps to maintain the concentration gradients of Na⁺ and K⁺ ions across the membrane, contributing to the negative charge inside the cell.

User DonutGaz
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