A&P

1. Axial Skeleton

2. Axial Skeleton
• Three major regions:
1) Skull
2) Vertebral Column
3) Bony Thorax
• Function: Supports the head, neck, and trunk,
and it protects the brain, spinal cord, and the
organs in the thorax

3. The Skull
• Cranial Bones
– Enclose and protect the brain
– Sites of attachment for head & neck muscles
• Facial Bones
– Form framework of the face
– Contain cavities for sense organs of sight, taste, and
smell
– Provide openings for air & food passage
– Secure the teeth
– Anchor muscles of facial expression

4. Cranium
• Consists of 8 bones:
– Frontal bone
– Occipital bone
– Sphenoid bone (keystone of the cranium)
– Ethmoid bone
– Parietal bones (paired)
– Temporal bones (paired)

11. Parietal Bones and the Major Sutures
• Sutures – immovable fibrous joints which unite
the bones of the skull
• The four largest sutures occur where the
parietal bones articulate (form a joint) with
other cranial bones:
1) coronal suture – at articulation with frontal
bone
2) sagittal suture – where parietal bones meet
superiorly at the cranial midline

12. Sutures cont.
3) lambdoid suture – at articulation with occipital
bone
4) squamous sutures – where parietal
bones and temporal bones meet on the
lateral aspect of skull

19. Facial Bones (14)
• Vomer
• Paired maxillae or maxillary bones
• Paired zygomatic bones
• Paired palatine bones
• Paired lacrimal bones
• Paired nasal bones
• Paired inferior nasal conchae
• Mandible

31. Vertebral Column
• Cervical Vertebrae – 7
• Thoracic Vertebrae – 12
• Lumbar Vertebrae – 5
• Sacral Vertebrae – 5 (fused to form single
sacrum)
• Coccyx – single bone formed from fusion of 4
vertebrae