Skeletal muscle structure. Artwork showing each component of a skeletal muscle. The muscle is composed of several bundles of muscle fibres,called fascicles (large tubes). Nerve cells (translucent blue) attach to these fibres and transmit electrical impulses from the brain to the muscle. Each fibre in a fascicle is made of several smaller fibres,called myofibrils (right). Each myofibril is composed of rows of sarcomeres,the contractile units of muscle. A sarcomere is composed of two types of filament: actin (green) and myosin (blue). These filaments overlap,giving the muscle its striated appearance. During contraction,myosin filaments pull actin filaments inwards towards the M line (yellow,in the centre of the sarcomeres),shortening the length of the muscle as a whole | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Dalhoff, Henning |
Bildgröße: | 5554 px × 3177 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |