Having looked at the bones of the skeleton and the joints between them we logically move on to consider the muscles which move the bones and then the nerves which control them. Muscle, however does other things besides moving bones. It is a contractile tissue, divided on histological structure into three types: • skeletal or striated. Under direct (Voluntary) nervous control • cardiac, also striated but specialised and confined to the heart • smooth or visceral. Not under direct (voluntary) nervous control. In walls of alimentary tract, blood vessels, arrector pili - slow and sustained response. Form and function • Smooth muscle usually occurs in flat sheets, sometimes wrapped around a viscus like a gut in circular and longitudinal layers, or arranged as a sphincter to close off a tube (as in the anus). • Skeletal: so called because often attached to bone, but not invariably. This is what the layman thinks of as a muscle. Muscle means little mouse in Latin, from the fancied
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