Axial Skeleton (Ch 7) Flashcards
What are the parts of the axial skeleton?
skull hyoid bone vertebral column thoracic cage -80 named bones
What are the functions of the axial skeleton?
- supports head, neck, and trunk
2. protects brain, spinal cord, and thoracic organs
Foramen
a hole in a bone
–> typically for nerves/blood vessels
Fossa
a depression in a bone
Process
projection from a bone, narrow or wide, protrudes from surrounding bone
Meatus
hole/tube-like structure
Canal
a groove/tube-like structure, passageway for nerves/blood vessels
The Skull
- 28 bones (complex!)
- mostly flat bones formed via intramembranous ossification
- bones united by sutures
- subdivides into cranial and facial divisions
What are sutures?
interlocking, immoveable joints
What are the functions of the cranial bones?
- protect brain
2. provide attachment for some head/neck muscles
What are the functions of the facial bones?
- form framework of face
- openings for passage of food/air
- hold the teeth
- anchor muscles of the teeth
What are the subdivisions of the cranium?
- Vault: superior, lateral, and posterior bones of the skull (including the forehead)
- Base: inferior part of the crainum
What are the bones of the cranium?
- Frontal
- Occipital
- Sphenoid
- Ethmoid
- Parietals (2)
- Temporals (2)
Coronal Suture
between the frontal and two parietal bones
Squamous Sutures
between temporal and parietal bones (lateral)
Lambdoid Suture
between parietal bones and occipital bone
Saggital Suture
runs along midline of skull, between parietal bones
Frontal Bone
- makes up forehead
1. Superciliary Arches: deep to eyebrows at superior edge of orbit
2. Labella: superior to bridge of nose, smooth medial part
Parietal Bones
- posterior to frontal bone, make up most of superior part of skull
- touch saggital/lambdoid sutures
Occipital Bone
- bone at back of head, posterior to cranium/cranial base
- foramen magnum
- occipital condyles
foramen magnum
large opening of occipital bone the allows spinal cord to pass and connect with the brain
occipital condyles
where the skull articulates with the vertebral column
Temporal Bones
- paired temporal bones house opening to ear, base of cheekbone
- 3 main regions: petrous, tympanic, squamous
- -> petrous best seen internally (contains middle/inner ear cavities)
- External Acoustic Meatus
- mastoid/styloid processes: sites of muscle attachment
- TMJ
External Acoustic Meatus
opening in tympanic region leading to middle/inner ear