Skeletal System:Axial Skeleton Lecture 6 Skeletal System:Axial Skeleton

The Complete Skeleton Axial skeleton Appendicular skeleton Skull Hyoid bone Vertebral column Thoracic (rib) cage Appendicular skeleton Limbs Girdles Fig. 7.1

Superior and Posterior Views of Skull or Cranium Fig. 7.5 External occipital protuberance Ligamentum nuchae: Helps keep head erect Nuchal lines: Neck muscle attachment

Lateral View of Skull Temporal lines (temporalis muscle) Mandible Fig. 7.6 Temporal lines (temporalis muscle) Mandible Condyle Coronoid process for temporalis muscle

Frontal View of Skull Optic foramen (optic nerve) Frontal bone Parietal bone Temporal bone Sphenoid bone Ethmoid bone Nasal bone Lacrimal bone Perpendicular plate of ethmoid bone Zygomatic bone Vomer Inferior nasal concha Maxilla Mandible Fig. 7.4 Optic foramen (optic nerve) Lacrimal groove (tears from eye to nasal capsule)

Inferior View of Skull Foramen magnum Occipital condyles Maxilla Hard palate Palatine bone Temporal process of zygomatic bone Zygomatic arch Zygomatic process of temporal bone Vomer Sphenoid bone Styloid process Mandibular fossa Temporal bone Jugular foramen Mastoid process Carotid canal Occipital condyle Foramen magnum Occipital bone External occipital crest Inferior nuchal line Superior nuchal line External occipital protuberance Fig. 7.8 Fig. 7.8 Foramen magnum Occipital condyles Jugular foramen, carotid canal Hard palate - maxilla and palatine

Hyoid Bone and Auditory Ossicles Unpaired No direct bony attachment to skull Attachment point for some tongue muscles Attachment point for neck muscles that elevate larynx during speech and swallowing Auditory ossicles Malleus, incus and stapes Fig. 7.26

Vertebra Parts Body Vertebral foramen Vertebral arch Superior and inferior articular processes Transverse process Articular facets for rib Spinous process Fig. 7.29

Vertebral Column Regions Cervical (7 vertebrae) Thoracic (12 vertebrae) Lumbar (5 vertebrae) Sacral bone (1) Coccygeal bone (1) Fig. 7.28

Cervical Vertebrae Atlas Axis First vertebra ‘yes’ motion Second vertebra Dens or odontoid process ‘no’ motion Fig. 7.30

Thoracic and Lumbar Vertebrae Table 7.5 Table 7.5

Sacrum and Coccyx Fig. 7.31

Review Question The spinal cord passes along the vertebral column through the _______ and enters the skull through the __________. Spinous process, mandibular fossa Body, occipital condyles Superior and inferior articular processes, jugular foramen Vertebral arch, carotid canal None of the above is correct

Thoracic Cage and Sternum Parts Thoracic vertebrae Ribs (12 pair) True False Sternum (manubrium, body) Fig. 7.32

Points to Remember Two major components of the human skeleton: Axial skeleton arranged along the medial axis Appendicular skeleton connects to the axial skeleton Skull consists of: 22 bones (single and paired) 6 auditory ossicles (3 each side) and 1 hyoid Vertebral column consists of: Cervicals (7) Thoracics (12) Lumbars (5) Sacrum (5, fused) Coccyx (3-5, fused) Rib cage has true (bone) ribs and false (cartilage) ribs

Questions?