The human skeleton can be divided into three main parts:
The skull is a bone structure that protects the brain and forms the face. It is made up of 22 separate bones, allowing it to grow and maintain its shape. These bones lie along lines called sutures, which can be seen in the skull of a baby or a young person, but gradually disappear around age 30.
Most cranial bones form pairs, one on the right side and one on the left side. To make the skull stronger, some of these pairs, such as those of the frontal, occipital, and sphenoid bones, fuse into a single bone. The most important pairs of cranial bones are the parietal, temporal, maxillary, zygomatic, nasal and palatine bones. The cranial bones are thin but, because of their curved shape, are very strong in relation to their weight - as with an eggshell or a motorcycle helmet.
Formed by the spine, ribs and sternum bone. The trunk and head form the axial skeleton.
Or backbone, it consists of 33 bones (the vertebrae). Overlapping the holes in the vertebrae form an inner tube along the spine where the nerve medulla is located.
Rib and Sternum Bone
The rib and sternal bone protect the heart, lungs, and major blood vessels. The rib cage musculature is responsible, together with the diaphragm, for respiratory movements. The ribcage is formed by the ribs, which are flat, curved bones that attach dorsally to the spine and ventrally to the sternum. Most people have 12 pairs of ribs. Some have an extra (more common in men than women). The last two pairs of ribs are attached to the spine, not attached to the sternum (the floating ribs).