EXAM 2 KIN 2500 PART 2 02 06 2015 Chapter 7 The Skeletal System The Axial Skeleton Bones of the adult skeleton 206 bones Grouped in 2 divisions o Axial skeleton 80 o Appendicular skeleton 126 The skull The skull contains 2 sets of bones o Cranial bones 11 form the cranial cavity o Facial bones 14 form the face General features of the skull Bones of the skull have numerous surface markings that aid in their identification o Holes through the bone foramina o Bony projections e g a spine Frontal bone forms facial icons Forehead Eye socket superior part Also forms much of the anterior part of the cranial floor Surface features of the frontal bone Frontal squama supraorbital margin supraorbital foramen supraorbital notch frontal sinuses Parietal Bones 2 Form much of the sides and roof of the cranial cavity Surface features external surfaces are convex curved arched Temporal bones form the inferior lateral part of the cranial floor plus part of the lateral wall near the ear Surface features zygomatic process zygomatic arch mandibular fossa mastoid process petrous portion auditory ossicles carotid foramen carotid artery jugular foramen jugular vein Zygomatic process is on the temporal bone temporal process is on the zygomatic bones Zygomatic process temporal process zygomatic arch Occipital bone forms much of the posterior wall and the posterior floor of the cranial cavity Prominent surface features Foramen magnum where the spinal cord meets the lower part of the brain occipital condyles external occipital protuberance ligamentum nuchae membrane runs down the spinal column and gives support to the head Sphenoid bone articulates with all other cranial bones providing considerable stability to the skull has a complex shape resembling a bat greater wings and lesser wings Surface features body sphenoid sinus sella turcica houses the pituitary gland tuberculum sellae hypophyseal fossa dorsum sellae Ethmoid bone Facial bones Nasal these are paired bones that form the bridge of the nose Lacrimal These are paired bones that form the anterior portion of the medial wall of the socket Palatine These are paired bones that form the posterior edge of the hard palate as well as portions of the eye socket and nasal cavity wall and floor Inferior nasal conchae All conchae help to swirl and filter air before it passes into the lungs Maxilla and zygomatic bone Mandible lower jaw Orbits 3 cranial bones and 4 facial bones form each orbit Associated with each orbit are 5 openings Paranasal sinuses These are cavities within frontal sphenoid and ethmoid bones The sinuses lighten the skull s mass and play a role in resonance Sutures An in adults immovable joint Coronal frontal and parietal Sagittal joins the parietal bones Lambdoid parietal and occipital bones Squamous between the parietal and temporal bones Fontanels at birth Cranial fossae three distinct regions called cranial fossae that correspond to the major contours of the inferior surface of the brain Hyoid bones 02 06 2015 02 06 2015