<P> Muscle fibers are in turn composed of myofibrils . The myofibrils are composed of actin and myosin filaments , repeated in units called sarcomeres , which are the basic functional units of the muscle fiber . The sarcomere is responsible for the striated appearance of skeletal muscle , and forms the basic machinery necessary for muscle contraction . </P>
<P> Muscle fibers are in turn composed of myofibrils . The myofibrils are composed of actin and myosin filaments , repeated in units called sarcomeres , which are the basic functional units of the muscle fiber . The sarcomere is responsible for the striated appearance of skeletal muscle , and forms the basic machinery necessary for muscle contraction . </P>
the functional unit of the skeletal muscle is the
the functional unit of the skeletal muscle is the
sarcomere
sarcomere