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Explain The Process Of Muscle Contraction

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Explain The Process Of Muscle Contraction
There are several steps that are needed to complete muscle contraction. First a neuron action send an impulse to the muscle. The motor neuron terminal releases the neurotransmitter acetylcholine (Ach) which triggers the impulse in the muscle. The electrical impulse is propagated down the sarcolemma then through the t-tubules that surrounds the myofibrils. Calcium is then released from the sarcoplasmic reticulum that eventually finds its way into the sarcoplasm then reaching the sarcomere. Calcium begins to bind to troponin (located on the actin filament, causing tropomyosin to move and expose binding sites for myosin. With the actin exposed, the myosin head now starts to bind to actin and forms a crossbridge. The myosin heads movement releases
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