Skull Anatomy Flashcards
1
Q
How many bones is the skull composed of ?
A
22
2
Q
how many groups is the skull divided into?
A
2 groups
3
Q
What are the two groups that the bones of the skull are divided into?
A
Cranial bones
Facial Bones
4
Q
How many cranial bones are there
A
8
5
Q
how many facial bones are there ?
A
14
6
Q
cranial bones are further subdivided into :
A
Calvaria and Floor
7
Q
What is the inner layer of spongy bone separating two outer plates of compact tissue
-composition of calvarium bones
A
Diploe
8
Q
cranial Bones of the calvaria
A
Frontal
Occipital
Right parietal
Left parietal
9
Q
Cranial bones of the floor
A
Ethmoid
Sphenoid
Right temporal
Left temporal
10
Q
The cranial floor is divided into three regions
A
-anterior cranial fossa
-middle cranial fossa
-posterior cranial fossa
11
Q
houses frontal lobes of cerebrum; extends from anterior frontal bone to lesser wings of sphenoid
A
Anterior cranial fossa
12
Q
houses temporal lobes; extends from lesser wings of sphenoid to apices of petrous ridges
A
Middle cranial fossa
13
Q
deep depression posterior to petrous ridges; protects cerebellum, pons, and medulla oblongata
A
Posterior cranial fossa
14
Q
fibrous joints that connect the bones of the skull
A
Sutures
15
Q
what suture is between frontal and parietal bones
A
coronal
16
Q
what suture is on top of head between two parietal bones
A
sagittal
17
Q
what suture is between temporal bone and parietal bones
A
squamosal
18
Q
what suture is between occipital and parietal bones
A
lambdoidal
19
Q
junction of coronal and sagittal sutures
A
Bregma
20
Q
junction of sagittal and lambdoidal sutures
A
Lambda
21
Q
areas of incomplete ossification in infant skulls (i.e., “soft spots”)
A
Fontanels
22
Q
what age is the adult cranial size usually achieved
A
age 12
23
Q
once was the sphenoidal fontanel
A
Pterion
24
Q
once was the mastoid fontanel
A
Asterion
25
The inner layer of spongy tissue found inside cranial bones is called :
Diploe
26
The fontanel located at the junction of the coronal and sagittal sutures is the
Bregma
or foramina
27
The two parietal bones articulate with the frontal bone to form what suture ?
Coronal
28
The cranial bone that provides a depression to house the pituitary gland is what bone
sphenoid
29
The fontanel located at the junction of the lamboidal and sagittal sutures is the ?
Lambda
30
The bone that forms the anterior portion of the cranium is what bone
Frontal
31
The cranial bone located between the orbits and posterior to the nasal bones is what bone
Ethmoid
32
The two parietal bones and the occipital bone joint together to form what suture
Lambdoidal
33
The anterior clinoid process is located on what bone
Sphenoid
34
Which bone contains the transmission of the olfactory nerves
Ethmoid
35
bones that are at the top of the skull
cranial
36
bones of the skull that are in the front
Facial bones
37
what is the plane that is front to back
coronal
38
what is the plane that is up and down
axial
39
what is the plane that is left and right
sagital
40
very top of the head
Bregma
41
what does the posterior fontanel become
the lambda
42
what does the frontal fontanel become
Bregma
43
what bone Has vertical portion (frontal squama) and horizontal portions
Frontal bone
44
what does the frontal squama form
Frontal squama forms forehead and anterior part of cranial vault
45
what does the horizontal portion of the frontal bone form?
Horizontal portions form orbital plates, part of roof of nasal cavity, and greater part of anterior cranial fossa
46
landmarks of the frontal bone :
Frontal eminences
Supraorbital margins
Supraciliary arches
Supraorbital foramina
Glabella
47
what bone Articulates with right and left parietals, sphenoid, ethmoid, nasal bones, and zygoma
Frontal bone
48
what fits in the ethmoidal notch ?
ethmoid
49
what does the ethmoid consist of :
Consists of
Horizontal plate
Vertical plate
Two light, spongy masses = labyrinths
50
what bone is Located between the orbits and forms part of anterior cranial fossa, nasal cavity, orbital walls, and bony nasal septum
Ethmoid bone
51
what is the horizontal portion of the ethmoid bone called?
cribriform plate
52
what part of the ethmoid bone is this: conical projection at anterior midline of cribriform plate
Crista galli
53
what part of the ethmoid is : vertical portion; forms superior portion of bony nasal septum
Perpendicular plate =
54
what part of the ethmoid bone contains numerous foramina for transmission of olfactory nerves
Cribriform plate
55
what part of the ethmoid bone is this:
Contain ethmoid sinuses or air cells
Walls form part of medial walls of orbits and lateral walls of nasal cavity
Have two thin, scroll-shaped projections = superior and middle nasal conchae
Labyrinths
56
what bone Articulates with frontal, sphenoid, lacrimal, maxilla, and vomer
Ethmoid bone
57
what part of the ethmoid bone will meet up with the vomer and make up the nasal septum
Perp. plate
58
what part of the parietal bone is this: prominent bulge near center of external surface of each bone
This is the point where the width of the skull should be measured to set technique
pariteal eminence
59
Somewhat square
Have a convex external surface and concave internal surface
Parietal Bones
60
what does the parietal bones articulate with
Articulate with:
each other at the sagittal suture in MSP, the frontal,
temporal,
occipital,
and sphenoid bones
61
Irregular, wedge-shaped bone that vaguely resembles a bat
sphenoid bone
62
Located in base of cranium anterior to temporal bones and basilar portion of occipital
sphenoid
63
what does the sphenoid consist of :
Body
Two lesser wings
Two greater wings
Two pterygoid processes
sella turcica
clivus
optical canal
dorsum sellae
posterior clinoid processes
64
Body contains two sphenoid sinuses and forms posterior bony wall of nasal cavity
Sphenoid bone
65
what part of the sphenoid is this:
deep depression on superior surface of body
sella turcica
66
what part of the sphenoid is this:
Houses pituitary gland
Located in MSP of cranium ¾ inch (1.9 cm) anterior and superior to external acoustic meatus (EAM)
sella turcica
67
names parts of the ethmoid bone :
labyrinths, cribiform plate, crista galli, perp plate
68
names parts of the parietal bone:
parietal eminence,
69
what part of the sphenoid is this: anterior border of sella
Tuberculum sellae
70
what part of the sphenoid is this: posterior border of sella
Dorsum sellae
71
what part of the sphenoid is this:
top borders of dorsum
Posterior clinoid processes
72
what part of the sphenoid bone is this:
slanted area of bone posterior and inferior to dorsum
Continuous with basilar area of occipital
Supports pons of the brain
Clivus
73
what part of the sphenoid bone is this:
opening into the apex of orbit for transmission of optic nerve and ophthalmic artery
Actual opening is termed optic foramen
optic canal
74
what wings of the sphenoid bone arise from anterior and superior portion of body and lie horizontally on each side
lesser wings
75
what part of the sphenoid bone Form posteromedial portion of orbital roofs, posterior portion of anterior cranial fossa, upper margin of superior orbital fissure, and optic canals
Medial ends form the anterior clinoid processes
lesser wings
76
what part of the sphenoid :
arise from sides of body and curve laterally, posteriorly, anteriorly, and superiorly
Form part of middle cranial fossa and posterolateral walls of orbit
greater wings
77
what part of the sphenoid bone arise from lateral portions of inferior surface of body and medial portions of inferior surfaces of greater wings
Pterygoid processes
78
which three paired foramina situated on greater wings
Rotundum
Ovale
Spinosum
79
what bone is Situated at posteroinferior part of cranium
Occipital bone
80
what bone Forms posterior half of cranial base and greater portion of posterior cranial fossa
Occipital bone
81
what are the four parts of the occipital bone
Squama
Two occipital condyles
Basilar portion
82
what part of the occipital bone has a = large opening through which medulla oblongata passes as it exits cranium
foramen magnum
83
what part of the occipital bone has a prominent process on squama
Also called inion
Corresponds to internal occipital protuberance
External occipital protuberance
84
what bone is Situated on each side of cranial base between greater wings of sphenoid and occipital bone
temporal bone
85
what bone Form large part of middle cranial fossa and a small part of posterior cranial fossa
temporal bone
86
what is the temporal bone consists of :
-Squamous portion
-Tympanic portion
-Styloid process
-Zygomatic process
-Petromastoid portion, which contains the organs for hearing and equilibrium
87
what part of the temporal bone is this:
= thin, upper portion of temporal bone
Forms part of side wall of cranium
temporal bone
88
what part of the temporal bone is this:
prominent arched process that projects anteriorly to articulate with zygoma and complete the zygomatic arch
Zygomatic process
89
what receives condyle of mandible to form temporomandibular joint (TMJ)
Mandibular fossa
90
91
what part of the temporal bone is this:
located below squama and in front of petromastoid portion
Forms anterior wall, inferior wall, and part of posterior walls of the EAM
Tympanic Portion
92
what part of the temporal bone is this: slender, pointed bone projecting inferiorly, anteriorly, and slightly medially from inferior surface of tympanic portion
styloid process
93
how is the sella turcica located
located in the MSP of cranium 3/4 inch anterior and superior to external acoustic meatus (EAM)
94
what projects medially and anteriorly between greater wing of sphenoid and occipital bone
Petrous portion
95
Conical or pyramidal in shape
Thickest and densest portion of cranium
Contains the organs of hearing and balance
petrous pyramid or petrous portion
96
conical process projecting from mastoid portion
mastoid process
97
bones of middle ear
Malleus
Incus
Stapes
Auditory ossicles
98
what does the temporal bone articulate with
the parietal, occipital, sphenoid, zygoma, and mandible
99
Three canals at right angles
semicircular canals
100
what view is to see optic canal
reese view
101
-sensory organ of ampulla
-hair cells and supporting cells
-rapid turns of head or body stimulate hair cells
semicircular canals
102
swelling of membranous labyrinth that communicates with the vestibule
semicircular canals
103
what is the thickest part of the skull ?
petromastoid portion
104
contains organs for hearing
temporal
105
what does the condyle of mandible fit into
the mandibular fossa
106
which cranial bones are paired?
temporal
107
the sella turcica is part of the :
sphenoid bone
108
which of the following bones are part of the cranial floor ?
1. ethmoid
2. frontal
3. temporal
1 and 3
