Context
The human skeleton is surrounded by the soft tissues of the body and is a living structure capable of adaption, growth and regeneration. In this way it differs from the non-living exterior skeletons of animals, such as insects, which have to be shed and replaced at each growth period of the animal.
The skeleton is made up of over 200 bones, joints, cartilages and ligaments. A major function of the skeleton is to provide shape and support to your body. Without this support our body would simply collapse. Shape and support does not mean posture! Posture is a function of the muscular system.
The bones provide movement by allowing muscles to attach to the bones. The shapes and relationships of bones where they join each other are a factor in determining the type of movement allowed by the joint.
The skeleton protects your various organs by forming protective walls and cavities, for example, your rib cage protects your heart and lungs and your skull protects your brain.
The bones are a source of blood supply. Both red and white blood cells are produced in the bone marrow. The bones are also a store for minerals (eg calcium and magnesium) required for body functions.