What is the sequence of events for muscle contraction?
· The myosin head attaches to the myosin binding site on the actin filament forming an actinomyosin bridge· ATP is hydrolysed to ADP and inorganic phosphate as the cross-bridge forms (ATP hydrolase is activated by calcium ions so that ATP is hydrolysed)· The myosin head tilts in a rowing action, sliding the actin filament over the myosin filament, toward the centre of the sarcomere· Energy from the hydrolysis of ATP causes the myosin head to release the actin filament· The myosin head flips back into its original position and the cycle is repeated as another actinomyosin bridge is formed.
LB
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