The Skull Kyle Franklin Megan Gleason Emily Giannotti Pages in Textbook

Cranial Sutures Sutures- lines at which 2 bones fuse together. These are the 4 on the cranium: – Coronal Suture- fuses parietal bones to frontal bone. – Lambdoidal Suture- fuses occipital bone to parietal bones (anteriorly). – Saggital Suture- fuses parietal bones in midline of skull. – Squamous Suture- fuses temporal bones to parietal bones.

Cranial Bones The cranium consists of 8 bones (1 st 3 are largest): – Frontal (1)- forms forehead, projections under eyebrows, superior part of eye orbits. – Parietal (2)- form most of superior and lateral walls of cranium.

Cranial Bones -Temporal (2)- lie inferior to parietal bones. Contain 5 important markings: -External auditory meatus- canal that leads to eardrum and middle ear. -Styloid process- needlelike projection, inferior to external auditory meatus, provides for muscle attachment. -Zygomatic Arch- thin bridge of bone that joins anteriorly with cheekbone (zygomatic bone). -Mastoid Process- rough projection, full of air cavities (mastoid sinuses), provides for muscle attachment. -Jugular Foramen- medial to styloid process, allows passage of jugular vein, which drains brain.

Cranial Bones – Occipital (1)- contains: Foramen Magnum- surrounds lower part of brain, allows spinal cord to connect to brain. Occipital Condyles- rest on the first vertebra of the spinal column. – Sphenoid (1)- most of this bone lies deep on the inferior aspect of the cranium. – Ethmoid (1)- irregular shape, anterior to sphenoid, forms rook of nasal cavity and part of medial walls of orbits. Christa Galli- projects from superior surface of ethmoid, outermost covering of brain attaches to it

Facial Bones Maxillary- fuses to form upper jaw and all facial bones except mandible join it. Zygomatic- (cheekbones) makes up a good portion of lateral walls of orbits. Lacrimal- (fingernail-sized bones) forms part of medial walls of orbits and allows passageway for tears. Nasal- small rectangular bone forming the bridge of the nose. Mandible- (lower jaw) largest and strongest facial bone.

Hyoid Bone Not technically part of the skull. Only bone in the body that does not articulate directly with any other bone. It is suspended in the mid-neck region. Function: moveable base for tongue and attachment point for the neck muscles that raise and lower the larynx when we swallow and speak.

References Beresford, W. (n.d.). 206 Nervous System. Anatomy Department. Retrieved November 18, 2009, from wberesford.hsc.wvu.edu/206CNS.htm Ph.D., B. B. (2003, December 12). h&n lateral skull - temporal bone - squamous part. SUNY Upstate Medical University. Retrieved November 17, 2009, from Cummings, B. (n.d.). Use the following blank diagrams. Georgia Highlands College. Retrieved November 18, 2009, from 7_axial.htm Lecture 9: Axial Skeleton I. (n.d.). Computing Services for Faculty & Staff. Retrieved November 17, 2009, from APA formatting by BibMe.org