Question

Which muscle protein binds with calcium ions that are released from the sarcoplasmic reticulum?

Answer 1

Calcium ions are stored in the sarcoplasmic reticulum (SR). As the muscle action potential travels along the sarcolemma and into the transverse tubule system, the ion channels open in the SR membrane. The calcium ions flood into the sarcoplasm around the thick and thin filaments. The ions bind the troponin muscle protein, causing it to change the shape of the muscle.