Attached to the skeleton are the muscles of the body. Although the skeleton provides the underlying framework, the muscles give the body its unique appearance. The importance of muscles is that they are needed for all body actions, ranging from moving to digestion and breathing.
There are three main types of muscles in the body. Each type has a special purpose that is vital to the normal functioning of the body.
Found in the bowel, the gut and internal organs. There is no direct control of this muscle - it works automatically.
Cardiac or heart muscle is specialised muscle that contracts constantly and automatically. Some factors can affect the speed of the contractions such as exercise and the release of hormones such as adrenaline. Further details of the heart can be found in the 'Circulatory System'.
Skeletal muscles are the ones that can easily be seen as a shape under the skin. Unlike smooth muscle or cardiac muscle, we can control skeletal muscles and because of this it is sometimes known as voluntary muscle.
The diagrams below show front and back views of the major skeletal muscles: