Number the events below 1 – 7 to represent the correct sequenceof events in skeletal muscle contraction and relaxation
___Ca2+ binds to troponin; tropomyosin moves, exposing theactive site of actin
___Acetylcholine (ACh) triggers an end-plate potential in themotor end plate.
___ The motor neuron stops releasing ACh andAcetylcholinesterase degrades the ACh in the synaptic cleft
___An Action potential in the sarcolemma travels down theT-Tubules
___ Ca2+ is released from the sarcoplasmic reticulum into thecytosol
___ The cytosolic concentration of Ca2+ returns to the restinglevel, the active sites of actin are blocked, and the muscle fiberrelaxes
___ Actin and myosin bind, and myosin undergoes a power stroke.ATP detaches actin and myosin, and the cycle repeats resulting incontraction of the muscle fiber
