The skull is comprised of flat bones (occipital parietal frontal, nasal and lacrimal) and the thoracic cavity (sternum and spine), and the pelvis (ilium and ischium). These bones are used to guard internal organs such the brain, heart the pelvic, pelvic, and. The flat bones are somewhat smooth and may https://health59157.blogspothub.com/9863289/what-are-the-ties-between-arthritis-and-bone-problems