Anatomy Lec 3 (Skeletal Axial) Flashcards
two divisions of the skeleton
- axial 2. appendicular skeleton
of bones in axial skeleton
80
of bones in appendicular skeleton
126
3 parts of axial skeleton
- cranium 2. vertebral column 3. bony thorax
Not included in axial (common misconception)
scapula, clavical
2 functions of the cranium
- encloses and protects the brain 2. provides attachment for head and neck muscles
5 functions of the face
- form framework 2. cavities for sensory organs 3. passage of air/food 4. teeth 5. anchor muscles of face
3 cranial fossae
- posterior 2. middle 3. anterior
2 divisions of cranium
vault and base
divides skull into distinct fossae
prominent bony ridges
3 sections of sphenoid
- zygomatic arch 2. lesser wing 3. greater wing
2 sections of superior ethmoid bone
- crista galli 2. cribiform plate
4 smaller cavities of the skull
- middle/inner ear 2. nasal cavity 3. orbits 4. air filled sinuses
how many openings in the skull
85
3 openings for important stuctures
spinal cord, blood vessels (for brain), 12 pairs of Cranial Nerves
of large bones in cranium
8
2 sets of paired cranial bones
- temporal 2. parietal
4 unpaired cranial bones
- frontal 2. occipital 3 sphenoid 4. ethmoid
Location of parietal bones
superior and latereral
4 Major sutures of the cranium
- cornoal 2. squamous 3. sagittal 4. lambdoid
2 bones making up coronal suture
parietal and frontal
2 bones that make up squamous suture
parietal and temporal
2 bones forming sagittal suture
left and right parietal bones meet superiorly
2 bones forming lambdoid suture
parietal and occipital
3 major structures of frontal bone
- supraorbital margin 2. glabella 3. frontal sinuses
Forms the posterior cranial fossa
occipital bone
5 structures of occipital bone
- occipital condyles 2. hypoglossal foramen 3. external occipital protuberance 4. superior nucah lines 5. inferior nuchal lines
Mastoid Process function
- sitre for neck muscle attachment 2. contains air sinuses
Petrous region
- projects medially, contributes to cranial base 2. houses cavities of middle/inter ear
4 foramina of the temporal bone
- jugular foramen 2. carotid canal 3. formane lacerum 4. internal acoustic meatus
Sphenoid bone functions
- spans width of cranial floor 2. resembles bat 3. 5 important openings 4. keystone of the cranium 5. body and thre pairs of processes
3 Sphenoid bone foramen
- rotundum 2. ovale 3. sphinsum
Location of ethmoid bone
- between nasal and sphenoid bones 2. forms most of the medial bony region between the nasal cavity and orbits
3 major internal ethmoid structures
- cribiform plate (olfactory foramina) 2. crista galli 3. perpendicular plate
Cribiform plate
superior surface of the ethmoid bone
Crista galli
attachment for falx cerebri
Perpendicular plate
forms superior part of nasal septum
Lateral masses of ethmoid bone
contain air cells
superior and middle nasal conchae (ethmoid bone)
extend medially from lateral masses
2 unpaired facial bones
- mandible 2. vomer
6 paired facial bones
- maxillae 2. zygomatic 3. nasal 4. lacrimal 5. palatine 6. inferior nasal conchae
3 anterior features of ethmoid
- lacrimal 2. middle nasal concha 3. perpendicular plate
2 components of mandible
- horizontal body 2. upright rami
4 maxillary bone features
- articulate with all other facial bones 2. contain maxillary sinuses (largest) 3. forms part of inferior orbital fissure 4. “Keyston” bones of the face
4 locations of air filled sinuses
- frontal bone 2. ethmoid bone 3. sphenoid bone 4. maxillary bones
Functions of paranasal sinuses
- lined with mucous membrane 2. lighten skull
3 functions of hyoid bone
- inferior to mandible 2. only bone with no bone articulation 3. acts as movable base for tongue
4 functions of thoracic cage
- framework of chest 2. protects organs 3. supports shoulder girdle & upper limbs 5. provides attachment sites for muscles
True ribs
1 - 7
False ribs
8 - 12
Floating Ribs
11 - 12
3 sections of sternum
- manubrium 2. body 3. xiphoid process
2 Disorders of the axial skeleton
- cleft palate 2. stenosis of lumbar spine
Cleft palate
- congenital disorder 2. right and left halves of palate fail to fuse medially
Stenosis
- narrowing of vertebral canal 2. compressed roots of spinal nerves
3 abnormal spinal curvatures
- scoliosis 2. kyphosis 3. lordosis
Scoliosis
abnormal lateral curvature
kyphosis
exaggerated thoracic curvature
lordosis
accentuated lumbar curvature ; swayback”
Axial skeleton development
- membrane bones ossify in second month development 2. bone tissue grows outward from ossification center 3. frontanels
frontanels
unossified remnants of membranes
