Approximately how many bones occur in the adult skeleton?
206
What are the 2 main divisions of the skeleton?
Axial and Appendicular
What are the 3 main components of the axial skeleton?
skull, vertebral column, thoracic cage
What are the 2 main divisions of the skull?
cranial, facial
What is the bone of the forehead?
frontal
What cavities hold the eyeballs?
orbits
What 2 large openings lie within these cavities?
superior orbital fissures
What is a synonym for the brow ridges?
superciliary ridges
What bones form the bridge of the nose?
left and right nasal bones
What bones form the upper jaw, the lateral walls of the nasal cavity, and the floor of the orbitals?
maxillae
What cavities lie within the maxillary bones inferior to the orbits?
maxillary sinuses
What bone forms the lower jaw?
mandible
What prominence on it forms the chin?
mental protuberance
What is the cavity of the nose?
nasal cavity
What prominence marks this cavity's anterior, inferior borders?
anterior nasal spine
What structure divides the nasal cavity into right and left halves?
nasal septum
What scroll-shaped bones are visible on the inferior lateral walls of this cavity?
inferior nasal conchae
What 4 bones can be seen in a superior view of the skull?
frontal bone, both parietal bones, occipital bone
What articulation between 3 of the 4 bones visible from a superior view of the skull occurs anteriorly in a frontal plane?
coronal suture
What articulation can be seen running along the midline in a superior view of the skull?
sagittal suture
What openings can be seen along the posterior 1/3 of the sagittal suture?
a single parietal foramen or paired parietal foramina
What is the clinical significance of the parietal foramina?
it conducts tiny emissary veins from the veins of the brain to the veins of the scalp. this provides a gateway for infection to the cranial cavity.
What articulation can be seen posteriorly in a frontal plane between 3 of the 4 bones visible from a superior view of the skull?
lambdoid suture
What 5 bones can be seen in a posterior view of the skull?
parietal bones, mandible, occipital bone, sutural bone
What is the bump on the midline on the posterior side of the skull?
external occipital protuberance
What are variable bones that commonly occur in the lamboidal suture and occasionally in other articulations within the skull?
sutural bones
What bones of the skull can be seen in the lateral view?
parietal bone, temporal bone, zygomatic bone, maxilla, frontal bone, mandible, occipital bone, ethmoid bone, lacrimal bone, nasal bone, sphenoid bone
What arch of bone can be seen in a lateral view of the skull?
zygomatic arch
What movable articulation can be palpated just anterior to the external auditory canal?
tempormandibular joint
What bump of bone occurs posterior to the ear?
mastoid process
What bones form the cranial cavity?
frontal, parietal, temporal, occipital, ethmoid, sphenoid
What sinuses can be seen in a midsagittal view of the skull?
frontal sinus, sphenoidal sinus
What structures can be seen in a midsagittal view of the skull as they form the nasal septum?
perpendicular plate, vomer
What bone separates the cranial cavity and the nasal cavity?
ethmoid bone
What 2 bones form the hard palate?
maxillae, palatine bone
In an inferior view of the skull what flat, wing-like structures of the sphenoid can be seen?
lesser and greater wings
What openings into the nasal cavity can be seen in an inferior view of the skull?
choanae
Through what opening of the skull does the mandibular division of the trigeminal nerve pass?
...
At what opening of the skull does the internal jugular vein begin?
jugular foramen
Through what opening in the skull does the internal carotid artery pass?
carotid canal
Through what opening in the skull does the spinal cord pass?
Foramen Magnum
With what smooth, rounded structures of the skull does the atlas articulate?
occipital condyles
What bone forms the anterior floor of the cranial cavity?
frontal bone
Through what portion of the ethmoid does the olfactory nerve pass?
cribriform plate
What portion of the sphenoid extend laterally from the body of the sphenoid?
...
What bone of the skull encases the ear?
...
Through what opening in the skull does the optic nerve pass?
optic canal
Through what opening in the skull does the cestibulococchlear nerve pass?
...
What are sutures?
immoveable joints that form the boundaries between the cranial bones
What suture extends across the superior surface of the skull along a coronal plane?
coronal suture
What suture extends like an arc across the posterior surface of the skull?
lambdoid suture
What suture lies along the midline superiorly on the skull?
sagittal suture
What suture lies laterally between the parietal bone and temporal bone on each side?
squamous suture
What bones may be found within sutures?
sutural bones
What is a synonym for "skullcap"?
calvaria
What bone forms part of the calvaria, the forehead, and the roof of the orbits?
frontal bone
What cavities lie within the frontal bone?
frontal sinuses
What part of the skull do the parietal bones form?
lateral walls and roof of the cranium
What part of the skull do the temporal bones form?
inferior lateral walls of the cranium floor
What part of the temporal bone holds the middle and inner ear?
petrous region
What opening occurs on the medial, posterior aspect of the temporal bone for blood vessels and nerves?
internal acoustic meatus
What is the posterior region of the temporal bone?
mastoid region
What prominence on the temporal bone lies posterior to the ear, serves as the insertion for the sternocleidomastoid, and contains air cells?
mastoid process
What region of the temporal bone surrounds the bony, external opening of the ear?
tympanic part
What thin point of bone on the temporal bone serves as an attachment for several hyoid and tongue muscles?
styloid process
What opening does the facial nerve pass through on the inferior surface of the skull?
stylomastoid foramen
What opening does the internal carotid artery pass through here?
carotid canal
What region of the temporal bone forms the superior, lateral, flat area of the bone?
squamous region
What bony process projects anteriorly from the squamous region of the temporal bone?
zygomatic process
What part of squamous region of the temporal bone articulates with the mandible?
mandibular fossa
What is the opening for the ear?
external acoustic meatus
What is the flat, posterior region of the occipital bone?
squamous region
What region of the occipital bone forms the base of the cranium?
basilar region
What is the large, circular opening within the skull for the spinal cord to pass through?
foramen magnum
What are the smooth, rounded projections on the left and right sides of the foramen magnum?
occipital condyles
Within the skull what is the opening for the cranial nerve XII?
hypoglossal canal
What superior, horizontal line projects laterally from the external occipital protuberance?
superior nuchal line
What is the thick, medial part of the sphenoid?
body
What cavities lie within the sphenoid?
sphenoidal sinuses
What projections of the sphenoid lie superior to the superior orbital fissure?
lesser wings
What projections of the sphenoid lie inferior to the superior orbital fissure and can be seen in a lateral view of the skull?
greater wings
Within the sphenoid what is the depression holding the pituitary gland?
hypophyseal fossa
What is the bony enclosure of the hypophyseal fossa?
sella turcica
Through what opening of the sphenoid does the optic nerve pass?
optic canal
What 3 foramina penetrate the greater wings of the sphenoid?
foramen rotundum, foramen ovale, foramen spinosum
What projections of the sphenoid provide attachment surfaces for some muscles that move the lower jaw and soft palate?
medial and lateral pterygoid processes
What is the superior, midsagittal elevation of the ethmoid?
crista galli
What horizontal structure of the ethmoid separates the cranial and nasal cavities?
cribriform plate
Through what openings do the olfactory nerves pass?
cribriform foramina
What parts of the ethmoid hold the ethmoidal sinuses?
ethmoidal labyrinths
What are the cavities within the ethmoid?
ethmoidal sinuses
What part of the ethmoid forms the medial wall of the orbits?
orbital plate
What scroll like extensions of the ethmoid project medially into the nasal cavity?
superior and middle nasal conchae
List 3 cranial fossae
anterior, middle, posterior
What is a synonym for the zygomatic bones?
cheekbones
What bony projections of the zygomatic bones contribute to the zygomatic arches?
temporal process
In addition to the temporal process, what other 2 processes articulate the zygomatic bone with surrounding bones?
maxillary process, frontal process
Where are the lacriminal bones located?
medial and anterior orbit walls
Within the lacriminal bone what structure allows the passage of the nasolacriminal duct?
lacrimal groove
The nasal bones form what facial feature?
bridge of the nose
The vomer helps to form what structure within the nasal cavity?
nasal septum
List 3 nasal conchae found on each side of the nasal cavity?
inferior, middle, superior
What is a synonym for the nasal conchae?
turbinate bones
What is the overall shape of the palatines?
L-shape
What portion of the palatines forms the posterior third of the hard palette?
horizontal plate
What part of the palatine forms the posterior, lateral wall of the nasal cavity?
perpendicular plate
What part of the palatine forms a small part of the floor of the orbit?
orbital process
What part of the maxilla forms the floor of the orbit?
...
What opening within the maxilla do the infraorbital artery and nerve pass through?
infraorbital foramen
What part of the maxilla holds the upper teeth?
alveolar process
What part of the maxilla forms the anterior 2/3 of the hard palette?
palatine process
What large cavity lies within the maxilla?
maxillary process
What is the horizontal portion of the mandible?
body
What are the ascending, posterior regions of the mandible?
rami
What part of the mandible holds the lower teeth?
alveolar process
What are the 2 corners of the mandible?
angle of the mandible
What opening lies on the anterolateral surface of the body of the mandible?
mental foramen
What opening within the mandible lies on the posterior, medial side?
mandibular foramen
What process of the mandible articulates with the temporal bone?
condylar process
What is the smooth round portion of the condylar process?
head of mandible
What is the joint between the mandible and the temporal bone?
temporomandibular joint
What process of the mandible does the temporalis insert on?
coronoid process
What is the U-shaped depression between the 2 mandibular processes?
mandibular notch
What bones make up the roof of the nasal cavity?
cribriform plate of the ethmoid bone, parts of the frontal and sphenoid bone
What bones make up the floor of the nasal cavity?
palatine processes of the maxillae, horizontal plates of the palatine bones
What bones form the lateral walls of the nasal cavity?
ethmoid bone, maxillae, inferior nasal conchae, perpendicular plates of the palatine bones, lacrimal bones
List the groups of paranasal sinuses
ethmoidal, frontal, maxillary, sphenoidal
List the bones that form the orbit
frontal bone, sphenoid bone, maxilla, zygomatic bone, palatine bone, lacrimal bone, ethmoid bone,
What is the collective term for the tiny bones of the middle ear?
auditory ossicles
List the ear ossicles from lateral to medial
malleus, incus, stapes
What small, U-shaped bone lies superior to the larynx?
hyoid bone
What is the anatomical term for the softspots in a baby's skull?
fontanelles
What is the function of the fontanelles?
to help fit the newborn baby's head through the birth canal
List the 4 fontanelles
mastoid, sphenoidal, posterior, anterior