Skeletal muscle is the tissue responsible for voluntary movement and is characterized by its striated appearance under microscopic examination. Structurally, it is composed of long, cylindrical fibers that are bundled together and connected to the skeleton. The fundamental unit of contraction is the sarcomere, which arises from the overlapping arrangement of protein filaments, notably actin and myosin. Contraction is initiated by an electrical signal from the nervous system, causing the filaments to slide past one another over a complex cycle of cross-bridge formation. This sliding action generates tension and force, enabling actions such as posture maintenance, locomotion, and the generation of heat, making it a critical component of physiological function.