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Muscle Contraction Report

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Muscle Contraction Report
During muscle contraction, groups of muscle fibres trigger a nerve to change the tension in the muscle. The first step in muscle contraction is the brain sending a message to the central nervous system, which in turn sends it to the peripheral nervous system then to the neuromuscular junction. The neurotransmitter, ACh is released into a space between the neuron and the muscle membrane. The action potential is generated altering the sarcolemma. This causes a change in the muscle membrane. As calcium ions are released during the resting phase, the binding sites of the tropomyosin located on the thin actin filaments are covered with troponins. ATP surrounds the thick myosin filament. When contraction happens, calcium ions bind to the troponin,

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