muscle

noun

fish have three types of muscles, cardiac (only in the heart), smooth (in the viscera, blood vessels or mixed with other tissues), and striated or skeletal (arranged to move the bones). Cardiac muscle has striations, branching fibres and nuclei in the centre of the fibres. Smooth muscle has unstriated fibres, centrally located nuclei and are smaller than striated muscles. Striated muscles has large, longitudinal fibres with cross striations and several, peripherally located nuclei.