KROK 1 2010 – Question 190 · KROK (Medicine) · Physiology
An isolated muscle fiber is under examination. It was established that the threshold of stimulation force became significantly lower. What is the cause of this phenomenon?
- A. Block of energy production in the cell
- B. Activation of sodium channels of membrane
- C. Inactivation of potassium channels of membrane
- D. Inactivation of sodium channels of membrane
- E. Activation of potassium channels of membrane
Hint
Think about what happens to excitability when the stimulus needed to trigger an impulse falls, and which ionic mechanism sets how easily an impulse starts.
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