The sarcoplasmic reticulum surrounds each sarcomere and pumps calcium. This calcium - triggers muscle contraction.
The sarcoplasmic reticulum
- is a complex network of the specialized smooth endoplasmic reticulum.
- important in transmitting the electrical impulse as well as in the storage of calcium ions.
- surrounds each sarcomere or the myocytes
- When the action potential propagates down the t-tubule, the voltage-sensitive proteins are activated
- which triggers the release of calcium ions (Ca++) from the sarcoplasmic reticulum.
- The Ca++ then initiates contraction, which is sustained by ATP
thus, The sarcoplasmic reticulum surrounds each sarcomere and pumps calcium. This calcium - triggers muscle contraction.
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