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module menu icon The skeleton

The skeleton

Standing, sitting, moving around… all activities that are generally taken for granted. But none would be possible without the musculoskeletal system.


The skeleton is one of the major structures of the musculoskeletal system and it is made up of over 200 bones. The axial skeleton protects the vital organs of the body, and is comprised of the skull, ribcage and spine. The appendicular skeleton is concerned with movement and consists of the shoulders, pelvic girdles, arms, legs, hands and feet. Both parts support and maintain the shape of the body.

Bones are strong but light and are made up of two different types of tissue. The outer layer is known as cortical or compact tissue and is almost solid in nature. Inside is a meshwork known as cancellous or trabecular tissue, within which bone marrow is stored. This part of the bone is spongy and has a rich blood supply. It is the location for the production of both red and white blood cells.

Bones are not static, but instead go through a continual process of resorption and formation. Resorption is the term used for the breakdown of mature bone tissue, which releases minerals such as calcium into the bloodstream, while formation describes the manufacture of new bone tissue, which picks up minerals in order to become strong.