KROK 1 2010 – Question 91 · KROK (Medicine) · Physiology
An isolated cell of human heart automatically generates excitement impulses with frequency of 60 times per minute. This cell was taken from the following heart structure:
- A. Ventricle
- B. Atrium
- C. Atrioventricular node
- D. Sinoatrial node
- E. His’ bundle
Hint
Intrinsic firing rate declines stepwise along the conduction system from its origin towards the lower chambers; use the given frequency to place the cell on that gradient.
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