Muscle is a form of tissue that primarily allows the movement or support to the body of many living organisms. It contains proteins actin and myosin that allows the muscle contraction and relaxation. According to the sliding filament theory, contraction/relaxation of muscles is a series of steps that require the use of energy to produce movement. Calcium ions regulate the binding of actin and myosin. Once the calcium ions are diffused in the sarcoplasm, the myosin binding site is exposed, allowing the binding of actin. as myosin binds with actin, the cross bridge is formed, splitting an ATP molecule into ADP (adenosine diphosphate) and an inorganic phosphate. ATP (adenosine triphosphate) is needed in order to supply the necessary energy for the contraction to happen.
The explanation is right. The muscle tissue has filaments called actin and myosin filaments.These filaments are muscle fibers that cause the muscle to contract and relax. The filaments interlace in such away that the actin filaments are found on the extremes and the myosin filaments are found on the middle. The calcium ions released from sarcoplasmic reticulum activates the actin filaments to attach to head of myosin filaments. The ATP found on myosin heads are dissociated in to ADP and P when the head is excited and release the energy needed to cause the the actin filaments move on myosin filaments from both sides of the extremes shortening the muscle (causing muscle contraction).