Axial Skeleton: Skull REAL

Total bones in adult body

206 bones with children having more bones that fuse over time

Axial skeleton

80 bones located along the longitudinal axis including skull hyoid vertebrae ribs sternum and auditory ossicles

Appendicular skeleton

126 bones including upper limbs lower limbs pelvic girdle and pectoral girdle

Girdles

Attachment sites connecting appendicular skeleton to axial skeleton

Surface features

Include ridges projections openings and depressions

Function structure link

Understanding function helps with memorization of bone features

Ridges

Raised areas that serve as muscle attachment points

Projections

Structures that extend from bone and serve as muscle and ligament attachment points

Openings

Passageways for blood vessels and nerves such as foramina and canals

Depressions

Indented regions that protect blood vessels and nerves such as fossae notches and grooves

Body of bone

Main portion of a bone

Neck of bone

Narrow region of a bone

Head of bone

Expanded end of a bone

Margin or border

Outer portion of a bone

Condyle

Smooth rounded surface for articulation

Facet

Small flattened surface for articulation

Skull function

Protects brain and supports organs of vision hearing taste and smell

Skull components

22 bones including cranial bones and facial bones

Cranial bones

8 bones forming brain case including frontal parietal occipital temporal sphenoid and ethmoid

Facial bones

14 bones including maxillary zygomatic palatine lacrimal nasal vomer and mandible

Mandible

Only movable bone of the skull

Temporal bone articulation

Temporal bone articulates with mandible at mandibular fossa

Ethmoid bone features

Includes perpendicular plate superior nasal conchae and middle nasal conchae

Palatine bone anterior view

Only a small portion is visible from the front

Zygomatic arch

Formed by temporal process and zygomatic process

Supraorbital margins

Provide protection for the eye orbit

Inferior nasal conchae

Separate bone within nasal cavity

Vomer

Forms inferior portion of nasal septum

Maxilla

Forms upper jaw floor of orbit nasal cavity and hard palate

Mandible description

Largest and strongest skull bone

Sphenoid bone

Butterfly or bat shaped bone forming large part of cranial floor

Palatine bone inferior view

L shaped bone contributing to hard palate

Temporal bone mastoid process

Rounded projection

Temporal bone external auditory meatus

Opening to ear canal

Temporal bone styloid process

Thin pointed projection

Temporal bone mandibular fossa

Depression where mandible attaches

Occipital bone external occipital protuberance

Bump on back of skull

Foramen magnum

Large opening for spinal cord

Occipital condyles

Structures that articulate with vertebrae

Orbit bones total

7 bones forming eye socket

Orbit roof

Formed by frontal and sphenoid bones

Orbit lateral wall

Formed by zygomatic and sphenoid bones

Orbit floor

Formed by maxilla zygomatic and palatine bones

Orbit medial wall

Formed by maxilla lacrimal ethmoid and sphenoid bones

Orbit shape

Cone shaped structure that allows muscle attachment

Hyoid bone location

Located below mandible and not part of skull

Hyoid bone structure

U shaped unpaired and floating bone

Hyoid bone function

Anchors tongue and neck muscles for speech and swallowing