Multiple Choice
Why can't tetanus occur in the heart?
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 contraction.
D) The heart contracts with maximal force every beat so it is impossible to increase the strength of its contraction.
E) Vagal stimulation slows down the heart rate to prevent summation of contractions.
Correct Answer:

Verified
Correct Answer:
Verified
Q82: Use the following answer code to indicate
Q83: The only veins in an adult that
Q84: Match the characteristic with the appropriate term(s).<br>a.tricuspid
Q85: Depolarization occurs at the AV node<br>A)during the
Q86: Indicate which valve abnormality is being described
Q88: Using the following answer code, indicate which
Q89: Using the following answer code, indicate which
Q90: Choose a correct sequence of blood flow
Q91: Use the answer code below to complete
Q92: A whistling murmur heard between the second