7 P A R T A The Skeleton

80 bones segregated into 3 regions The Axial Skeleton 80 bones segregated into 3 regions ______________________________

Bones of the Axial Skeleton Figure 7.1

The Skull Cranium Facial bones protects the ______________________________ site of attachment for ______________________________ Facial bones framework of the ______________________________ ______________________________ Provide openings for passage _____________________________ Anchor the facial muscles of emotion expression

Anatomy of the Cranium 8 cranial bones – Cranial bones ______________________________ ________________________________________________ Cranial bones Thin Very strong

Frontal Bone Figure 7.2a

Frontal Bone Forms ______________________________ portion of the cranium Articulates posteriorly with the parietal bones via the ______________________________

Lateral View Figure 7.3a

Occipital Bone and Its Major Markings Forms most of skull’s posterior ______________________________ Figure 7.2b

Temporal Bones Form the ______________________________ aspects of the skull and parts of the cranial floor

Temporal Bones Figure 7.5

Sphenoid Bone Forms the central wedge that _____________________ with all other cranial bones -butterfly-shaped

Sphenoid Bone Figure 7.6b

Ethmoid Bone Figure 7.7

Ethmoid Bone Most ____________________ of the skull bones Forms most of the bony area between the __________________________________________________________________________________

Sutural Bones Tiny irregularly shaped bones that appear within sutures Not all skulls have them Result of additional _____________ center during fetal development

Facial Bones ____________ bones _________________________________- unpaired maxillae, zygomatics, nasals, lacrimals, palatines, and inferior conchae - paired

Mandible and Its Markings The mandible (lower jawbone) is the largest, strongest bone of the face

Maxillary Bones Medially _________________ bones that make up the upper jaw and the central portion of the facial skeleton

Zygomatic Bones Irregularly-shaped bones ______________________________

Other Facial Bones Nasal bones – thin bones that form the ______________________________ Lacrimal bones – contribute to the medial walls of the ______________________________; houses the lacrimal sac (lets tears drain from eye surface into nasal cavity) Palatine bones – two bone plates that form the ______________________________ walls of the nasal cavity, and a small part of the orbits

Other Facial Bones _________________________ – plow-shaped bone that forms part of the nasal cavity ______________________________ – paired, curved bones in the nasal cavity that form part of the lateral walls of the nasal cavity

Anterior Aspects of the Skull Frontal bone Parietal bone Glabella Frontal squama of frontal bone Frontonasal suture Supraorbital foramen (notch) Nasal bone Supraorbital margin Sphenoid bone (greater wing) Superior orbital fissure Temporal bone Optic canal Ethmoid bone Inferior orbital fissure Lacrimal bone Zygomatic bone Middle nasal concha Perpendicular plate Infraorbital foramen Ethmoid bone Maxilla Inferior nasal concha Vomer bone Mandible Mental foramen (a) Mandibular symphysis Figure 7.2a

Posterior Aspects of the Skull Sagittal suture Parietal bone Sutural bone Lambdoid suture Occipital bone Superior nuchal line External occipital protuberance Mastoid process Inferior nuchal line Occipitomastoid suture External occipital crest Occipital condyle (b) Figure 7.2b

External Lateral Aspects of the Skull Coronal suture Frontal bone Sphenoid bone (greater wing) Parietal bone Ethmoid bone Temporal bone Lacrimal bone Lambdoid suture Lacrimal fossa Squamous suture Nasal bone Occipital bone Zygomatic process Zygomatic bone Occipitomastoid suture Maxilla External acoustic meatus Mastoid process Alveolar margins Styloid process Mandibular condyle Mandible Mandibular notch Mental foramen Mandibular ramus (a) Mandibular angle Coronoid process Figure 7.3a

Midsagittal Lateral Aspects of the Skull (b) Parietal bone Coronal suture Frontal bone Frontal sinus Sphenoid bone (greater wing) Crista galli Nasal bone Sphenoid sinus Ethmoid bone (perpendicular plate) Vomer bone Maxilla Mandible Alveolar margins Incisive fossa Lambdoid suture Occipital bone Occipitomastoid suture External occipital protuberance Internal acoustic meatus Sella turcica of sphenoid Pterygoid process of sphenoid Mandibular foramen Palatine Squamous Temporal maxilla Figure 7.3b

Inferior Portion of the Skull Maxilla (palatine process) Incisive fossa Medial palatine suture Hard palate Infraorbital foramen Palatine bone (horizontal plate) Maxilla Zygomatic bone Sphenoid bone (greater wing) Temporal bone (zygomatic process) Foramen ovale Vomer Foramen lacerum Mandibular fossa Carotid canal External acoustic meatus Styloid process Stylomastoid foramen Mastoid process Jugular foramen Temporal bone (petrous part) Occipital condyle Pharyngeal tubercle of basioccipital Inferior nuchal line Parietal bone Superior nuchal line External occipital crest External occipital protuberance Foramen magnum (a) Figure 7.4a