Question

Discuss the specific role of ATP in muscle contraction. and give me the good conclusion of that

Answer 1

Muscle contraction happens in the presence of the Calcium ions in the sarcoplasm. Calcium ions bind to a protein called troponin that leads to confirmation change in it. This confirmation change causes uncovering of the myosin binding site on the actin filament. Myosin has binding sites for actin that is myosin head and it also has site for ATP binding. ATP that is bound to myosin gets hydrolysed and the products ADP and P​​​​​​i bound to the myosin. Now myosin has potential energy due to ATP hydrolysis and once myosin binding site on the actin is uncovered in the presence of calcium ions myosin head binds to actin filament. This is known as cross bridge formation. Now myosin head moves towards M line pulling actin filament along with it. This is known as power stroke. As actin filament move towards M line, contraction of muscle happens. As myosin head move towards M line, ADP and P​​​​​​i released from the myosin protein. Then binding of new ATP leads to detachment of myosin head from the actin binding site. This cycle keeps repeating during muscle contraction in the presence of calcium ions.