Multiple Choice
Why is the sinoatrial node the heart's normal pacemaker
A) It has the fastest natural rate of autorhythmicity.
B) It has both sympathetic and parasympathetic innervation.
C) It is under the control of AV node.
D) Activation of K⁺ channels occurs more rapidly in this region than elsewhere in the heart.
Correct Answer:
Verified
Correct Answer:
Verified
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