PHYSIOLOGY
MUSCLE CONTRACTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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ACh breakdown, depolarize, Ca pump
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Depolarize, ACh breakdown, Ca pump
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Ca pump, depolarize, ACh breakdown
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None of the above
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Detailed explanation-1: -Relaxation of a Skeletal Muscle Relaxing skeletal muscle fibers, and ultimately, the skeletal muscle, begins with the motor neuron, which stops releasing its chemical signal, ACh, into the synapse at the NMJ. The muscle fiber will repolarize, which closes the gates in the SR where Ca++ was being released.
Detailed explanation-2: -AChE decomposes ACh and the muscle fiber membrane is no longer stimulated. Potassium ions leave the muscle cell causing repolarization. Calcium ions are actively transported back into the sarcoplasmic reticulum. Linkages between actin and myosin filaments break. Actin and myosin filaments slide apart. More items
Detailed explanation-3: -Ca++ pumped back in sarcoplasmic reticulum. release of Ca++ from troponin. cessation of interaction between actin and myosin.
Detailed explanation-4: -Depolarisation and calcium ion release. Actin and myosin cross-bridge formation. Sliding mechanism of actin and myosin filaments. Sarcomere shortening (muscle contraction)