The skeletal system has main two parts:
- The axial skeleton
- The appendicular skeleton
- Skull
- Backbone
- Ribs
- Breastbone
The backbone has 33 separate different size and shaped vertebrae. Its surrounds and protects the spinal cord.
The 12 pairs of flat bones make up the rib basket. It supports the chest wall, prevents it from collapsing when the diaphragm contracts.
The Appendicular skeleton bones are those of:
- Arms
- Legs
The appendicular are nothing but pelvic girdle, which has three fused hipbones, pectoral girdle has two collarbones and scapulas are shoulder blades.
Joints
There are four types of joints that allow the free movement of the body parts
- The Ball and socket allows the free movement between humerus & scapula; and femur & hipbone
- Hinge joint allows movement in a single plane for instance knee joint
- Pivot joint allows the movement between ball and socket and hinge joint, also found in wrists and ankles.
The joins of skull are very strong and immovable.