KROK 1 2019 – Question 38 · KROK (Medicine) · Physiology
What changes can be expected to occur in the isolated heart of a toad, if excessive amount of calcium chloride is introduced into its perfusate?
- A. Increased cardiac contraction force and frequency
- B. Decreased cardiac contraction force
- C. Increased cardiac contraction force
- D. Increased cardiac contraction frequency
- E. Diastolic cardiac arrest
Hint
Think about the dual role of calcium ions in the heart: in the working myocardium and in the pacemaker tissue.
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