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The relaxation of skeletal muscle fibers and the skeletal muscle, itself, begins with the motor neuron, which stops releasing its

chemical signal, Ach, into the synapse at the neuromuscular junction. The muscle fiber will repolarize. What is the next step in
relaxation?

User Zerumi
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Answer:Muscle contraction usually stops when signaling from the motor neuron ends, which repolarizes the sarcolemma and T-tubules, and closes the voltage-gated calcium channels in the SR. Ca++ ions are then pumped back into the SR, which causes the tropomyosin to reshield (or re-cover) the binding sites on the actin strands. A muscle also can stop contracting when it runs out of ATP and becomes fatigued (

Step-by-step explanation:

User Mbabramo
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