MICROANATOMY

Detailed explanation-1: -Muscle contraction entails the sliding of the thin filaments past the thick filaments, resulting in shortening of the sarcomere and, thus, the entire myocyte. The resulting longitudinal force is transmitted through the extracellular matrix (ECM) to the bone via the tendon.

Detailed explanation-2: -Mechanical force is generated within skeletal muscle cells by contraction of specialized myofibrillar proteins.

Detailed explanation-3: -Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past each other, which is called the sliding filament model of muscle contraction. ATP provides the energy for cross-bridge formation and filament sliding.

Detailed explanation-4: -During contraction, the myosin heads extend from the thick filament surface and attach to actin in the thin filaments, causing the filaments to slide past each other in a cyclic, ATP-driven process.

Detailed explanation-5: -Actin filaments, usually in association with myosin, are responsible for many types of cell movements. Myosin is the prototype of a molecular motor-a protein that converts chemical energy in the form of ATP to mechanical energy, thus generating force and movement.