Neurocranium Flashcards
frontal
front most bone of the neurocranium
surpaorbital notch/foramen
notch/hole in eyebrow bone
supercilliary arches
eyebrow arches bone
lacrimal fossa
indentation inside the orbital for the lacrimal gland duct
supraorbital nerve
goes through supraorbital notch
ethmoid notch
for olfatory nerves to smell
function of the frontal
forms the anterior cranial fossa to support and protect the frontal lobe
frontal is _____ type of bone
dermal bone
development of frontal
develops in utero to from 2 separate ossification centers,
divided by metopic suture
metopic suture
between to sides of the frontal
portions of frontal
squamous, orbital and nasal
parietal
a pared bone that articulates at the sagittal suture
temporal lines
for the temporalis muscle (for chewing)
middle meningeal arteries
attaches to the inside of the parietals and has a groove in which it sits
sagittal sinus
see diagram
parietal eminence
only present in adults but origianally an ossification center from which each parietal (dermal bone) develops in utero
occipital
back of skull; both dermal and endochondral; single midline bone
foramen magnum
large hole in center of occipital
hypoglossal canal
comes from foramen magnum and goes under occipital condyle
occipital condyle
has 2 pieces (1 on each side and is anterior to the foramen magnum)
jugular foramen
largeish holes lateral to the foramen magnum
function of occipital
forms the posterior cranial fossa and protects the cerbellum (visual info prcessed there)
devel of the occipital
four portions:
1-basilar part
2-lateral parts (2 of them)
3- central squamous portion
4- lateral squamous portions
3&4 are dermal from a single ossification center
1 and 2 are endochondral (cartilage that calcifies)
foramen magnum placement
in center in humans because were bipedal
temporal
paired bone at side that includes ear area and cheekbone
zygomatic arch
cheekbone
mastoid process
attaches to mastoid area posterior to auditory meati
glenoid fossa
holds mandible in place
carotid canal
area/hold that ineranl carotid artery goes through that is lateral to foramen magnum
ear ossicles
stapes, incus and malleus
malleus attaches to ear drum while stapes is deeper and attaches to inner ear. incus is right between
devel. of temporal
squamous portion is dermal, petorus and mastoid portions are endochondral, styloid process and ear ossicles come from branchial arches
sagittal suture
between 2 parietal bones; separates left from right
coronal suture
separates frontal from parietals; separates front from back
labdoid suture
shaped like lambda, separates parietals from occipital
metopic suture
ususally not present in adults but separates frontals/is where they articulate
squamosal sutures
separates temporal from parietal
dermal bones made from what…?
mesenchyme
endochondral bones made from…?
cartilage
why are sutures present?
they are joints that allow for growth via bone deposition at their edges; deposition is in response to forces exerted by growing brain
fontanelles
soft spots
membranous gaps between growing cranial bones
important fontanelles
anterior fontanel (last to close over)
sphenoid fontanel
mastoid fontanel
posterior fontanel
sinuses
cavities within certain bones around the nasal cavity that are lines with mucous membranes
how are sinuses formed
through excavation of bone by air-filled sacs from the nasal cavity
craniosynostosis
premature sutural fusion; brain continues to grow and therefore deforms the skull
