The
skeletal system is the internal support and movement
system composed
bones, joints, cartilage and
ligaments. Bones have various
functions including:
- Support –Support the body against gravity
- Protection – Keep the soft internal organs “packed” safely inside the body; internal organs are easily injured
- Movement – Limbs act as rigid levers against which muscles can work
- Storage – Fat, minerals (Calcium)
- Blood cell formation – Hematopoiesis in the marrow
There are two main
divisions in the
skeletal system related to both their
location and
function.
The
axial skeleton is found along the longitudinal (vertical) axis of the body, and includes the skull and vertebrae.
The
appendicular skeleton includes the bones of the limbs and the girdles to support the limbs.
Figure 5.1.1 Divisions of the skeletal system. The axial skeleton consists of the skull, vertebral column, ribs and sternum (shown in yellow). The appendicular system consists of the limbs and limb girdles (shown in blue).