Myofilaments

From Biology-Online Dictionary | Biology-Online Dictionary

myofilaments

The ultramicroscopic threads of filamentous proteins making up myofibrils in striated muscle. Thick ones contain myosin and thin ones actin; thick and thin myofilaments's also occur in smooth muscle fibres but are not regularly arranged in discrete myofibrils and thus do not impart a striated appearance to these cells.