When an action potential arrives at the neuromuscular junction, acetylcholine is released into the synaptic cleft and binds to receptors in the postsynaptic membrane.Which of the following represents the correct order of the next series of events?
A) Calcium is released from the sarcoplasmic reticulum, an action potential travels down the T tubules, depolarization spreads through the T tubule, and myosin binds actin.
B) An action potential travels down the T tubules, depolarization spreads through the T tubule, calcium is released from the sarcoplasmic reticulum, and myosin binds actin.
C) An action potential travels down the T tubules, depolarization spreads through the T tubule, calcium is taken up by the sarcoplasmic reticulum, and myosin binds actin.
D) An action potential travels down the T tubules, depolarization spreads through the T tubule, ATP binds to myosin, and myosin binds actin.
E) A T tubule is depolarized, calcium is released from the sarcoplasmic reticulum, an action potential is created in the muscle cell, and myosin binds actin.

Question

Quizplus · Accepted Answer

The correct order of events following the binding of acetylcholine to receptors in the postsynaptic membrane is: 1) an action potential travels down the T tubules, 2) depolarization spreads through the T tubule, 3) calcium is released from the sarcoplasmic reticulum, and 4) myosin binds actin. This sequence of events leads to muscle contraction. Option B correctly reflects this sequence of events.

When an Action Potential Arrives at the Neuromuscular Junction, Acetylcholine