The Skull
• Two parts of the skull:
– The cranium encloses and protects the brain
– The facial bones hold the eyes and face shape
• Eight large flat bones fused together (sutures):
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Frontal – forms forehead
Parietal – superior and lateral walls (paired)
Temporal – inferior to parietal, at temples (paired)
Occipital – posterior wall
Sphenoid – deep to the anterior of skull, forms
floor of cranial cavity
– Ethmoid – forms roof of nasal cavity, medial walls
of orbits
• Thirteen bones fused together, with one
connected by joints
– Maxillae – forms upper jaw (paired)
– Palatine – posterior to maxillae, between back
molars (paired)
– Zygomatic – cheekbones, lateral walls of orbits
(paired)
– Lacrimal – part of medial walls of orbits, between
ethmoid bones and maxillae (paired)
• Continued…
– Nasal – bridge of nose (paired)
– Vomer – median line of nasal cavity
– Inferior conchae – bone projections from lateral
wall of nasal cavity (paired)
– Mandible – lower jaw, connected by only freely
movable joint of face
• Hyoid Bone
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Not technically part of skull
Does not articulate directly with any other bone
Anchored to temporal bones by ligaments
Movable base for tongue
Attachment point for neck muscles
• Bone Markings
– Meatus – canal-like passageway
• External Auditory Meatus – canal leads to eardrum
and middle ear (temporal)
– Process – bony prominence
• Styloid Process – inferior to auditory meatus
(temporal)
• Zygomatic Process – anterior to cheek bone
(temporal)
• Mastoid Process – posterior and inferior to auditory
meatus (temporal)
• Palatine Processes – extensions of maxillae that
form the anterior part of the mouth (maxillae)
– Foramen – opening through bone
• Jugular Magnum – at junction of occipital & temporal
bones, opening for jugular vein (temporal)
• Carotid Canal – anterior to jugular foramen, opening
for carotid artery (temporal)
• Foramen Magnum – opening for spinal cord to
connect to brain (occipital)
• Foramen Ovale – opening for nerve fibers to pass to
jaw muscles (sphenoid)
– Condyle – rounded articular projections (involved with
joints)
• Occipital Condyles – rest on the first vertebra of the
spinal column (occipital)
– Sinuses – cavities in bone filled with air
• Paranasal Sinuses – found in different bones
surrounding nasal cavity (frontal, ethmoid, sphenoid,
maxillae)