Question

How does calcium affect the process of muscle contraction?

Answer 1

Calcium is the ion responsible for unmasking of active sites of actin filaments leading to cross bridge formation and muscle contraction. As the impulse passes through sarcolemma it reaches sarcoplasmic reticulum and results in release of Ca++ into sarcoplasam. Ca++ attach with troponin-C resulting in moving of tropomyosin away from the active sites of actin permitting cross bridge formation.