Ch. 11 Skull Flashcards
the skull is divided into these two sets of bones, how many are in each
8 cranial bones
14 facial bones
the bones of the cranium are divided into these two sections
- calvarium (skullcap)
- floor
what are the bones of the floor of the skull
- right temporal
- left temporal
- sphenoid
- ethmoid
what are the bones of the calvarium (skullcap)
- frontal
- left parietal
- right parietal
- occipital
what are the two main parts of the frontal bone
- squamous/vertical portion
- orbital/horizontal portion
this main part forms the forehead
squamous/vertical portion
this main part forms the superior part of the orbit
orbital/horizontal portion
smooth, raised prominence between the eyebrows just above the bridge of the nose
glabella
slight depression above each eyebrow
supraorbital groove (SOG)
the supraorbital groove (SOG) corresponds to what
floor of the anterior fossa of the cranial vault
what is the supraorbital groove (SOG) also at the level as
orbital plate (highest level of the facial bone mass)
superior rim of each orbit
supraorbital margin (SOM)
small hole or opening within the SOM slightly medial to its midpoint
supraorbital notch (foramen)
what passes through the supraorbital notch
supraorbital nerve and artery
on each side of the squamous portion of the frontal bone above the SOG is a larger, rounded prominence called what
frontal tuberosity (eminence)
what does the orbital/horizontal portion of the frontal bone consist of
- supraorbital margin (SOM)
- superciliary ridges
- glabella
- frontal tuberosities
forms the superior part of each orbit
orbital plate
each orbital plate is separated from the other by this
ethmoidal notch
what bones do the frontal bone articulate with
4 cranial bones
- R and L parietals
- sphenoid
- ethmoid
(8 facial bones)
the lateral walls of the cranium and part of the roof are formed by these bones
parietal bones
these bones are roughly square and have a concave internal surface
parietal bones
where is the widest portion of the entire skull located
between parietal tubercles (eminences) of the parietal bones
where are the greater wings of the sphenoid located in relation to the parietals
inferior and anterior
what bones do the parietals articulate with
5 cranial bones
- frontal
- occipital
- temporal
- sphenoid
- opposite parietal
the inferoposterior portion of the calvarium is formed by this
occipital bone
the external surface of the occipital bone presents a rounded part called what
squamous portion
prominent bump or protuberance at the inferoposterior portion of the skull
occipital protuberance, or inion
forms most of the back of the head and is the part of the occipital bone that is superior to the external occipital protuberance, or inion
squamous portion
the large opening at the base of the occipital bone through which the spinal cord passes as it leaves the brain
foramen magnum
oval processes with convex surfaces, with one on each side of the foramen magnum
two lateral condylar portions (occipital condyles)
what is the two part articulation between the skull and the cervical spine called
atlantooccipital joint
what type of joints are the atlantooccipital joints
ellipsoidal joints
what bones does the occipital bone articulate with
6 bones
- 2 parietals
- 2 temporals
- sphenoid
- atlas
complex structures that house the delicate organs of hearing and balance
temporal bones
what are the temporal bones situated between
- greater wings of sphenoid anteriorly
- occipital bone posteriorly
extending anteriorly from the squamous portion of the temporal bone is an arch of bone called what
zygomatic process
the zygomatic process meets the temporal process of the zygomatic bone to form this
zygomatic arch
inferior to the zygomatic process and just anterior to the external acoustic (auditory) meatus (EAM) is what
temporomandibular (TM) fossa
projecting inferior to the mandible and anterior to the EAM is a slender bony projection called what
styloid process
how many sections is the temporal bone divided into
3 primary parts
- squamous
- mastoid
- petrous
thin upper portion of the temporal bone that forms part of the wall of the skull; quite thin and most vulnerable portion of the entire skull to fracture
squamous portion