Skeleton Functions And Tissue Types

The skeleton has five main functions: protection, support and shape, movement, storage and production of blood cells.

Bones protect internal organs. The skull protects the brain, the spine protects the spinal cord, the thorax protects the heart and lungs and the pelvic girdle protects the reproductive organs.

Bones support the weight of the whole body. Cartilage shapes structures such as the ear and the nose. The skeleton provides the body with shape and forms a frame under the skin. The skeleton helps to maintain upright posture.

The body is held in position by muscles which are attached to the bones. Bones are linked at the joints and muscles allow them to move.

Blood cells are made in the red bone marrow in the centre of certain bones of the skeleton. The main sites of blood cell production are the pelvic girdle, ribs, sternum and the vertebrae.

The main mineral that is stored in the skeleton is calcium. The skeleton is continually replacing itself. Calcium is transported in the bloodstream to the sites of bone growth or where replacement is needed.

There are usually 206 named bones in an adult skeleton. These bones can be divided into two groups: the axial skeleton and the appendicular skeleton. The 80 bones of the axial skeleton include the bones of the head, vertebral column, ribs and breastbone or sternum. The appendicular skeleton consists of 126 bones and includes 64 bones in the shoulders and upper limbs and 62 are in the pelvis and the lower limbs. The appendicular skeleton makes body movement possible and protects the organs of digestion, excretion, and reproduction.

There are four main types of tissue. Epithelium tissue, connective, muscle and nervous tissue. Epithelium tissue is composed of layers of cells that cover organ surfaces such as surface of the skin and the inner lining of the