Substance a Is Found to Be a Competitor with Acetylcholine

question 187

Multiple Choice

Substance A is found to be a competitor with acetylcholine. Which step of muscle contraction physiology would be directly affected by this substance?

• A) Exposure of the active sites on G actin
• B) Release of acetylcholine from the presynaptic terminal
• C) Generation of an action potential at the sarcolemma
• D) Release of the myosin head following the power stroke

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