Week 3: Skull Flashcards
(274 cards)
What’re the 3 general functions of the skull?
- containment - brain, special senses (eyes, ears, olfaction 2. openings - nasal/ oral cavities 3. vocalisation - via paranasal sinuses
How does the structure of the nasal cavity relate to its function?
The shelves of bone on the lateral walls of the nasal cavity are curled and complex. This increases the SA and turbulence. Along with this they are lined with a mucous membrane, and perfused by blood vessels close to the surface of the cavity. The result of this is the humidification and filtering of air as it passes through.
What comprises the ‘masticatory apparatus’?
-teeth -moving jaw -muscles attached
The oral cavity will ____ in size during swallowing.
reduce
Detail the structure of the paranasal sinuses.
Sinuses are air filled cavities lined with mucous membranes. There are 4 paranasal sinuses, found in the ethmoid, maxillary, frontal and sphenoid bones (named accordingly). All the paranasal sinuses drain into the nasal cavity, which is lined with a similar mucous membrane.
Detail the function of the paranasal sinuses. (3)
- Projection of voice 2. Crash barrier for brain (absorb impact, less chance of brain damage) 3. Lightens the skull
what are the moving parts of the skull? what types of joints are these?
- mandible - at temperomandibular joint (TMJ) 2. ossicles - in middle ear The TMJ and ossicles are synovial joints.
What sort of joint are sutures? What sort of fibres link the articulating bones of the suture?
Sutures are fibrous joints, in which the bones are linked by collagen fibres.
What are the 5 ‘useful landmarks for ID of sutures’?
- Pterion - H shaped, thin and vulnerable, 4 bone intersection near temple 2. Nasion - T shaped, between eyes 3. Lambda - greek letter λ, where sagittal suture meets parieto-occipital suture 4. Bregma - T shaped, where coronal suture meets sagittal 5. Vertex - highest point
What’re the 3 ways in which sutures can be named?
- plane - coronal or sagittal 2. specific bones - ie. the parieto-occipital suture (AKA lamboid suture) 3. other features - ie. sutural (wormian) bones, bones which are found within the sutures themselves
Define fontanelle.
a soft spot remaining at the junction of sutures that usually closes after birth
t/f: some sutures/ fontanelles dissapear during development (life) of human.
true
some sutures/ fontanelles dissapear during development (life) of human - example?
- frontal suture 2. mental suture
simplest way to divide up what makes the skull? (simplified version)
skull = cranium + mandible
complex way to divide up the skull? (not simplified)
skull = cranium (braincase, 8 bones) + facial (14 bones) + ossicles (6 bones)
What comprises the neurocranium?
-bony case for the brain (hint: ‘neuro’) -8 bones -made of… 1.) calvaria (skull cap) - flat bones, frontal bone, parietal bone and occipital bone 2.) cranial base (floor, basicranium) - irregular bones with flat portions
What comprises the viscerocranium?
-facial skeleton -14 bones -surround mouth, nose, and orbit (eyes)
Define neonate.
a newborn baby
How does the skull proportion of a neonate compare to that of an adult? How about an ape? (note: skull proportion as in viscerocranium : neurocranium).
neonate 1:10 adult 1:3 ape 1:1
A neonate has a much greater sized neurocranium relative to its viscerocranium. What 3 developments occur to bring this ratio to a more even level throughout the life of a human?
Essentially this is due to the facial skeleton growing more then the calvaria (skull cap) post birth. Specifically… 1. teeth (including teeth support) 2. paranasal sinuses 3. some points still cartilagenous (will ossify w/ age, ie. external auditory canal) (???)
The cranium can be divided into neurocranium and viscerocranium. The neurocranium can be divided into ______ and _____.
calvaria (skull cap) and cranial base (floor)
What types of bones make up the skull cap? Specifically, what bones does the skull cap include?
flat bones parietal, occipital and frontal bones
What types of bones make up the cranial base?
irregular bones (which have flat portions)
What is the ‘frame of reference’ for divisions of the skull?
the Orbito-meatal plane (AKA Frankfort plane)

























































































































