Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Axial Skeleton Figure 7–1 The Axial Skeleton.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Axial Skeleton  The axial skeleton  Forms the longitudinal axis of the body  Has 80 bones  The skull: –8 cranial bones –14 facial bones –(1 hyoid and 6 middle ear bones)  The vertebral column  24 vertebrae (singular = vertebra)  The sacrum  The coccyx  The bony thorax  24 ribs  The sternum

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Axial Skeleton  Functions of the Axial Skeleton  Supports and protects organs in body cavities  Attaches to muscles of  Head, neck, and trunk  Respiration  Appendicular skeleton

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Skull  The skull protects  The brain  Entrances to respiratory system  Entrance to digestive system  The skull contains 22 bones  8 cranial bones:  Form the braincase or cranium  14 facial bones:  Protect and support entrances to digestive and respiratory tracts

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Skull Figure 7–2 Cranial and Facial Subdivisions of the Skull.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Skull  The 8 Cranial Bones  Occipital bone  Parietal bones (2)  Frontal bone  Temporal bones (2)  Sphenoid  Ethmoid

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The 14 Facial Bones of the Skull  The Facial Bones  Maxillae (maxillary bones) (2)  Nasal bones (2)  Zygomatic bones (2)  Lacrimal bones (2)  Mandible (1)  Inferior Nasal Conchae (2)  Vomer (1)  Palatine (2)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Skull Figure 5.7

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Bones of the Skull Figure 5.11

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Human Skull, Superior View Figure 5.8

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Human Skull, Inferior View Figure 5.9

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Occipital Bone  Back/bottom of skull  Contains foramen magnum where spinal cord attaches

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Parietal Bones  Has sutures (threadlike lines) that connect bones of the skull  Meets frontal coronal suture  Meets temporal squamous suture  Meets occipital lamboid suture  Meets 2 sagittal suture

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Frontal bone  Forms forehead

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Temporal Bones a.EXTERNAL ACOUSTIC (AUDITORY) MEATUS Leads to eardrum b.STYLOID PROCESS Neck muscle attachment point c.ZYGOMATIC PROCESS Attaches cheek bone (aka sphenoid) d.MASTOID PROCESS Air cavities (aka mastoid sinuses) High risk of infection e.JUGULAR FORAMEN Passage for jugular vein that is used for drainage f.INTERNAL ACOUSTIC (AUDITORY) MEATUS Transmits c.n VII (facial) and VIII (vestibulocochlear) g.CAROTID CANAL Carotid artery runs through Supplies blood

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Sphenoid  Behind eye  Contains sella turcica (aka Turk’s saddle) that holds pituitary gland in place  Foramen ovale allows c.n. V (trigeminal) that work with chewing muscle to pass  Optic canal allows optic nerve to pass to eye  Superior orbital fissure allows c.n. II (optic), IV (trochlear), and VI (abducens) to pass  Sphenoid sinuses are filled with air

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Cranial Bones of the Skull  Ethmoid  Roof of the nasal cavity  Crista galli where brain attaches  Cribriform plates (ie:holey plates)allow nerve fibers carrying olfactory (smell) receptors to reach brain  Middle concha allows air flow

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Facial Bones of the Skull Maxillae  main face bones  Alveolar margins hold teeth –Mandible and maxilla are responsible  Support upper teeth  Maxilla (palatine process) makes up roof of mouth

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Facial Bones of the Skull  Nasal Bones  Upper bone…lower cartilage  Vomer is in the inferior part of the nasal septum

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Facial Bones of the Skull  Zygomatic Bone  Cheek bones

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Facial Bones of the Skull  Lacrimal Bones  above nose…interior eye  Makes passageway for tears

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Facial Bones of the Skull  Mandible  Forms chin  Only free moving facial bone: moves lower jaw

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Paranasal Sinus Uses  Lighten skull  Give resonance/amplification to voice Figure 5.10

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Hyoid Bone  Not really part of the skull  Only “free” bone because it does not interact with any other bones  Moveable base for the tongue for speech and swallowing Figure 5.12

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column  The spine or vertebral column  Protects the spinal cord  Supports the head and body  26 bones  24 vertebrae, the sacrum, and the coccyx

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column Figure 7–16 The Vertebral Column.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column  Vertebrae  The neck  Seven cervical vertebrae  The upper back  12 thoracic vertebrae  Each articulates with one or more pair of ribs  The lower back  Five lumbar vertebrae  Remember: (Meal times )

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Intervertebral discs  Intervertebral discs  Pads that cushion and absorb shock  “S” shaped structure and discs prevent shock to head during normal activities (ex: walking/running) and provide flexibility

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Curvatures  Four Curvatures of the Vertebral Column  Primary curvature  Thoracic curve  Sacral curve  Secondary curvature  Cervical curve  Lumbar curve

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column Figure 7–17 Abnormal Curvatures of the Spine.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column Figure 7–18c Vertebral Anatomy.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column Figure 7–18 Vertebral Anatomy.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Vertebral Column Figure 7–18 Vertebral Anatomy.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Vertebral Regions  Regions of the Vertebral Column  Cervical (C)  Thoracic (T)  Lumbar (L)  Sacral (S)  Coccygeal (Co)

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Cervical Region  C1-C7  C1…..atlas  No body  allows for nodding “yes”  C2…..axis  Has “dens” (aka odontoid process)  allows for nodding “no”  Supports the atlas  Has heavy spinous process  attaches muscles of head and neck  Axis and atlas bodies fuse during development to form the dens  Intervertebral foramina (C3-C7)  Gaps between pedicles of adjacent vertebrae  For nerve connections to spinal cord

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Cervical Region  Intervertebral foramina (C3-C7)  Gaps between pedicles of adjacent vertebrae  For nerve connections to spinal cord  Vertebra prominens (C 7 )  Transitions to thoracic vertebrae  Has a long spinous process with a broad tubercle  Has large transverse processes

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Cervical Region Figure 7–19 The Cervical Vertebrae.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Region  Thoracic vertebrae (T 1 –T 12 )  Have heart-shaped bodies  Long, slender spinous processes  Attaches to ribs

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Vertebral Regions Figure 7–20b The Thoracic Vertebrae.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Vertebral Regions Figure 7–20c The Thoracic Vertebrae.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Lumbar Region  Lumbar vertebrae (L 1 –L 5 )  Largest vertebrae  Oval-shaped bodies  Sturdiest because it has the most stress

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Lumbar Region Figure 7–21b The Lumbar Vertebrae.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Lumbar Region Figure 7–21c The Lumbar Vertebrae.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Sacrum Region  sacrum  Is curved, more in males than in females  Protects reproductive, urinary, and digestive organs  Interacts with L5 superiorly (above) and coccyx inferiorly (below)  Makes up posterior wall of pelvis

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Coccyx Region  The coccyx  Attaches ligaments and a constricting muscle of the anus  Mature coccyx  Consists of three to five fused coccygeal vertebrae  First two coccygeal vertebrae:  Have transverse processes  Have unfused vertebral arches  Coccygeal cornua  Formed by laminae of first coccygeal vertebra

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Vertebral Regions Figure 7–22 The Sacrum and Coccyx.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax)  Functions of the Thoracic Cage  Protects organs of the thoracic cavity  Heart, lungs, and thymus  Attaches muscles  For respiration  Of the vertebral column  Of the pectoral girdle  Of the upper limbs

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Consists of: 1.Sternum (breastbone) 2.Ribs 3.Thoracic vertebrae

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) 1.Sternum  A flat bone  In the midline of the thoracic wall  Three parts of the sternum  Manubrium (jugular notch) –a shallow indentation on top of sternum –Interacts with clavicles (collarbones) and with cartilages of first rib pair  Sternal body –Attaches to the manubrium –Attaches to costal cartilages of ribs 2–7  Xiphoid process –Attaches to the sternal body –Attaches to diaphragm and rectus abdominis muscles

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Figure 7–23a The Thoracic Cage.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) 2.Ribs  Are mobile  Can absorb shock  Functions of ribs  Rib movements (breathing): –affect width and depth of thoracic cage –changing its volume

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax)  Ribs  Are 12 pairs of long, curved, flat bones  Extending from the thoracic vertebrae  Ribs are divided into two types  True ribs = 1 st 7 pairs attach directly to the sternum by costal cartilage  False ribs = 8-12 attached indirectly to sternum or not at all  Floating = 11-12

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Figure 7–23b The Thoracic Cage.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Figure 7–24c The Ribs.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Figure 7–24a The Ribs.

Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Thoracic Cage (Bony Thorax) Figure 7–24b The Ribs.