Why is extracellular calcium needed in cardiac muscle contractions, and why is it important in delaying repolarization?

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Medical Sciences

Whyis extracellular calcium needed in cardiac muscle contractions, andwhy is it important in delaying repolarization?

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Cardiac muscles have cardiomyocytes composed of tubular myofibrils These myofibrils have repeating sections of sarcomeres Contraction of cardiac muscle requires calcium induced calcium release that is conducted via the intercalated disc Cardiac cells are linked to each other by gap junctions Similar to skeletal muscle the action potential occurs in the muscle cells of the ventricle by the entry of sodium ions across the sarcolemma However depolarization can only be sustained for longer duration when there is an inward influx of calcium ions These calcium ions will flow via See Answer

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