Multiple Choice
Why can't tetany of the heart occur?
A) there are no distinct motor units in the heart.
B) there is inadequate oxygen supply via the coronary circulation to metabolically support a sustained contraction.
C) the refractory period in cardiac muscle lasts almost as long as the duration of the resultant contraction.
D) the heart contracts with maximal force every beat so it is impossible to increase the strength of cardiac contraction.
E) vagal stimulation slows down the heart rate to prevent summation of contractions.
Correct Answer:
Verified
Correct Answer:
Verified
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