MUSCLE PHYSIOLOGY

Detailed explanation-1: -Sarcomeres. A sarcomere is the functional unit (contractile unit) of a muscle fiber. As illustrated in Figure 2-5, each sarcomere contains two types of myofilaments: thick filaments, composed primarily of the contractile protein myosin, and thin filaments, composed primarily of the contractile protein actin.

Detailed explanation-2: -Skeletal muscles are composed of striated subunits called sarcomeres, which are composed of the myofilaments actin and myosin.

Detailed explanation-3: -An individual sarcomere contains many parallel actin (thin) and myosin (thick) filaments.