When a Pacemaker Potential in the SA Node Reaches Threshold

question 65

Multiple Choice

When a pacemaker potential in the SA node reaches threshold,

• A)the permeability to K⁺ ions increases.
• B)many voltage-gated Ca²⁺ channels open.
• C)voltage-gated Ca²⁺ channels close.
• D)RMP has been restored.
• E)permeability of the cell does not change.

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