In: Anatomy and Physiology
Ans:-
1. Role of calcium in muscle contraction is as follows:-
- Calcium ion plays an important role in muscle contraction by creating interactions between proteins, actin and myosin.
- The calcium ions binds to the C component of the actin filament , which exposes the binding site for the myosin head to bind to in order to stimulate a muscle contraction.
2. Role of ATP in muscle contraction is as follows:-
- ATP binds to the myosin causing it to change position and attach to actin and pull, causing muscle to contract . Without ATP muscles could not contract as one part of the muscle could not attach to the other.
3. Importance of hydrolysis of ATP in muscle contraction is as follows:-
- ATP is hydrolysed into ADP and inorganic phosphate (Pi) by the enzyme ATPase.
- The energy that is released during hydrolysis of ATP changes the angle of the myosin head into a "cocked" position , that is ready to bind to actin if the sites are available.