Contraction of cardiac muscle typically requires:
A. Ca++ influx through voltage-gated Ca++ channels to trigger a rise in cytosolic [Ca++]
B. Ca++ influx through voltage-gated Ca++ channels, which is sufficient to support contraction
C. activation of MLCK
D. phosphorylation of myosin heavy chain
E. Ca++ influx through the Na+-Ca++ antiporter
ANS: A
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Answer the following statement true (T) or false (F)
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