KROK 1 2007 – Question 58 · KROK (Medicine) · Physiology
Heart rate of a man permanently equals 40 beats pro minute. What is the pacemaker?
- A. Purkinje’s fibers
- B. His’ bundle branches
- C. Sinoatrial node
- D. Atrioventricular node
- E. His’ bundle
Hint
Recall the automaticity gradient: each level of the conduction system has its own intrinsic rate, falling from the atria toward the ventricles; match 40 per minute to its level.
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