upper border of mandibular body that contains the lower teeth
alveolar process of the maxilla
curved, inferior margin of the maxilla that supports and anchors the upper teeth
angle of the mandible
rounded corner located at outside margin of the body and ramus junction
angle of the rib
portion of rib with greatest curvature; together, the rib angles form the most posterior extent of the thoracic cage
anterior (ventral) sacral foramen
one of the series of paired openings located on the anterior (ventral) side of the sacrum
anterior arch
anterior portion of the ring-like C1 (atlas) vertebra
anterior cranial fossa
shallowest and most anterior cranial fossa of the cranial base that extends from the frontal bone to the lesser wing of the sphenoid bone
anterior longitudinal ligament
ligament that runs the length of the vertebral column, uniting the anterior aspects of the vertebral bodies
anulus fibrosus
tough, fibrous outer portion of an intervertebral disc, which is strongly anchored to the bodies of the adjacent vertebrae
appendicular skeleton
all bones of the upper and lower limbs, plus the girdle bones that attach each limb to the axial skeleton
articular tubercle
smooth ridge located on the inferior skull, immediately anterior to the mandibular fossa
atlas
first cervical (C1) vertebra
axial skeleton
central, vertical axis of the body, including the skull, vertebral column, and thoracic cage
axis
second cervical (C2) vertebra
body of the rib
shaft portion of a rib
brain case
portion of the skull that contains and protects the brain, consisting of the eight bones that form the cranial base and rounded upper skull
calvaria
(also, skullcap) rounded top of the skull
carotid canal
zig-zag tunnel providing passage through the base of the skull for the internal carotid artery to the brain; begins anteromedial to the styloid process and terminates in the middle cranial cavity, near the posterior-lateral base of the sella turcica
cervical curve
posteriorly concave curvature of the cervical vertebral column region; a secondary curve of the vertebral column
cervical vertebrae
seven vertebrae numbered as C1–C7 that are located in the neck region of the vertebral column
clavicular notch
paired notches located on the superior-lateral sides of the sternal manubrium, for articulation with the clavicle
coccyx
small bone located at inferior end of the adult vertebral column that is formed by the fusion of four coccygeal vertebrae; also referred to as the “tailbone”
condylar process of the mandible
thickened upward projection from posterior margin of mandibular ramus
condyle
oval-shaped process located at the top of the condylar process of the mandible
coronal suture
joint that unites the frontal bone to the right and left parietal bones across the top of the skull
coronoid process of the mandible
flattened upward projection from the anterior margin of the mandibular ramus
costal cartilage
hyaline cartilage structure attached to the anterior end of each rib that provides for either direct or indirect attachment of most ribs to the sternum
costal facet
site on the lateral sides of a thoracic vertebra for articulation with the head of a rib
costal groove
shallow groove along the inferior margin of a rib that provides passage for blood vessels and a nerve
cranial cavity
interior space of the skull that houses the brain
cranium
skull
cribriform plate
small, flattened areas with numerous small openings, located to either side of the midline in the floor of the anterior cranial fossa; formed by the ethmoid bone
crista galli
small upward projection located at the midline in the floor of the anterior cranial fossa; formed by the ethmoid bone
dens
bony projection (odontoid process) that extends upward from the body of the C2 (axis) vertebra
ear ossicles
three small bones located in the middle ear cavity that serve to transmit sound vibrations to the inner ear
ethmoid air cell
one of several small, air-filled spaces located within the lateral sides of the ethmoid bone, between the orbit and upper nasal cavity
ethmoid bone
unpaired bone that forms the roof and upper, lateral walls of the nasal cavity, portions of the floor of the anterior cranial fossa and medial wall of orbit, and the upper portion of the nasal septum
external acoustic meatus
ear canal opening located on the lateral side of the skull
external occipital protuberance
small bump located at the midline on the posterior skull
facet
small, flattened area on a bone for an articulation (joint) with another bone, or for muscle attachment
facial bones
fourteen bones that support the facial structures and form the upper and lower jaws and the hard palate
false ribs
vertebrochondral ribs 8–12 whose costal cartilage either attaches indirectly to the sternum via the costal cartilage of the next higher rib or does not attach to the sternum at all
floating ribs
vertebral ribs 11–12 that do not attach to the sternum or to the costal cartilage of another rib
fontanelle
expanded area of fibrous connective tissue that separates the brain case bones of the skull prior to birth and during the first year after birth
foramen lacerum
irregular opening in the base of the skull, located inferior to the exit of carotid canal
foramen magnum
large opening in the occipital bone of the skull through which the spinal cord emerges and the vertebral arteries enter the cranium
foramen ovale of the middle cranial fossa
oval-shaped opening in the floor of the middle cranial fossa
foramen rotundum
round opening in the floor of the middle cranial fossa, located between the superior orbital fissure and foramen ovale
foramen spinosum
small opening in the floor of the middle cranial fossa, located lateral to the foramen ovale
frontal bone
unpaired bone that forms forehead, roof of orbit, and floor of anterior cranial fossa
frontal sinus
air-filled space within the frontal bone; most anterior of the paranasal sinuses
glabella
slight depression of frontal bone, located at the midline between the eyebrows
greater wings of sphenoid bone
lateral projections of the sphenoid bone that form the anterior wall of the middle cranial fossa and an area of the lateral skull
hard palate
bony structure that forms the roof of the mouth and floor of the nasal cavity, formed by the palatine process of the maxillary bones and the horizontal plate of the palatine bones
head of the rib
posterior end of a rib that articulates with the bodies of thoracic vertebrae
horizontal plate
medial extension from the palatine bone that forms the posterior quarter of the hard palate
hyoid bone
small, U-shaped bone located in upper neck that does not contact any other bone
hypoglossal canal
paired openings that pass anteriorly from the anterior-lateral margins of the foramen magnum deep to the occipital condyles
hypophyseal (pituitary) fossa
shallow depression on top of the sella turcica that houses the pituitary (hypophyseal) gland
inferior articular process
bony process that extends downward from the vertebral arch of a vertebra that articulates with the superior articular process of the next lower vertebra
inferior nasal concha
one of the paired bones that project from the lateral walls of the nasal cavity to form the largest and most inferior of the nasal conchae
infraorbital foramen
opening located on anterior skull, below the orbit
infratemporal fossa
space on lateral side of skull, below the level of the zygomatic arch and deep (medial) to the ramus of the mandible
internal acoustic meatus
opening into petrous ridge, located on the lateral wall of the posterior cranial fossa
intervertebral disc
structure located between the bodies of adjacent vertebrae that strongly joins the vertebrae; provides padding, weight bearing ability, and enables vertebral column movements
intervertebral foramen
opening located between adjacent vertebrae for exit of a spinal nerve
jugular (suprasternal) notch
shallow notch located on superior surface of sternal manubrium
jugular foramen
irregularly shaped opening located in the lateral floor of the posterior cranial cavity
kyphosis
(also, humpback or hunchback) excessive posterior curvature of the thoracic vertebral column region
lacrimal bone
paired bones that contribute to the anterior-medial wall of each orbit
lacrimal fossa
shallow depression in the anterior-medial wall of the orbit, formed by the lacrimal bone that gives rise to the nasolacrimal canal
lambdoid suture
inverted V-shaped joint that unites the occipital bone to the right and left parietal bones on the posterior skull
lamina
portion of the vertebral arch on each vertebra that extends between the transverse and spinous process
lateral pterygoid plate
paired, flattened bony projections of the sphenoid bone located on the inferior skull, lateral to the medial pterygoid plate
lateral sacral crest
paired irregular ridges running down the lateral sides of the posterior sacrum that was formed by the fusion of the transverse processes from the five sacral vertebrae
lesser wings of the sphenoid bone
lateral extensions of the sphenoid bone that form the bony lip separating the anterior and middle cranial fossae
ligamentum flavum
series of short ligaments that unite the lamina of adjacent vertebrae
lingula
small flap of bone located on the inner (medial) surface of mandibular ramus, next to the mandibular foramen
lordosis
(also, swayback) excessive anterior curvature of the lumbar vertebral column region
lumbar curve
posteriorly concave curvature of the lumbar vertebral column region; a secondary curve of the vertebral column
lumbar vertebrae
five vertebrae numbered as L1–L5 that are located in lumbar region (lower back) of the vertebral column
mandible
unpaired bone that forms the lower jaw bone; the only moveable bone of the skull
mandibular foramen
opening located on the inner (medial) surface of the mandibular ramus
mandibular fossa
oval depression located on the inferior surface of the skull
mandibular notch
large U-shaped notch located between the condylar process and coronoid process of the mandible
manubrium
expanded, superior portion of the sternum
mastoid process
large bony prominence on the inferior, lateral skull, just behind the earlobe
maxillary bone
(also, maxilla) paired bones that form the upper jaw and anterior portion of the hard palate
maxillary sinus
air-filled space located with each maxillary bone; largest of the paranasal sinuses
medial pterygoid plate
paired, flattened bony projections of the sphenoid bone located on the inferior skull medial to the lateral pterygoid plate; form the posterior portion of the nasal cavity lateral wall
median sacral crest
irregular ridge running down the midline of the posterior sacrum that was formed from the fusion of the spinous processes of the five sacral vertebrae
mental foramen
opening located on the anterior-lateral side of the mandibular body
mental protuberance
inferior margin of anterior mandible that forms the chin
middle cranial fossa
centrally located cranial fossa that extends from the lesser wings of the sphenoid bone to the petrous ridge
middle nasal concha
nasal concha formed by the ethmoid bone that is located between the superior and inferior conchae
mylohyoid line
bony ridge located along the inner (medial) surface of the mandibular body
nasal bone
paired bones that form the base of the nose
nasal cavity
opening through skull for passage of air
nasal conchae
curved bony plates that project from the lateral walls of the nasal cavity; include the superior and middle nasal conchae, which are parts of the ethmoid bone, and the independent inferior nasal conchae bone
nasal septum
flat, midline structure that divides the nasal cavity into halves, formed by the perpendicular plate of the ethmoid bone, vomer bone, and septal cartilage
nasolacrimal canal
passage for drainage of tears that extends downward from the medial-anterior orbit to the nasal cavity, terminating behind the inferior nasal conchae
neck of the rib
narrowed region of a rib, next to the rib head
notochord
rod-like structure along dorsal side of the early embryo; largely disappears during later development but does contribute to formation of the intervertebral discs
nuchal ligament
expanded portion of the supraspinous ligament within the posterior neck; interconnects the spinous processes of the cervical vertebrae and attaches to the base of the skull
nucleus pulposus
gel-like central region of an intervertebral disc; provides for padding, weight-bearing, and movement between adjacent vertebrae
occipital bone
unpaired bone that forms the posterior portions of the brain case and base of the skull
occipital condyle
paired, oval-shaped bony knobs located on the inferior skull, to either side of the foramen magnum
optic canal
opening spanning between middle cranial fossa and posterior orbit
orbit
bony socket that contains the eyeball and associated muscles
palatine bone
paired bones that form the posterior quarter of the hard palate and a small area in floor of the orbit
palatine process
medial projection from the maxilla bone that forms the anterior three quarters of the hard palate
paranasal sinuses
cavities within the skull that are connected to the conchae that serve to warm and humidify incoming air, produce mucus, and lighten the weight of the skull; consist of frontal, maxillary, sphenoidal, and ethmoidal sinuses
parietal bone
paired bones that form the upper, lateral sides of the skull
pedicle
portion of the vertebral arch that extends from the vertebral body to the transverse process
perpendicular plate of the ethmoid bone
downward, midline extension of the ethmoid bone that forms the superior portion of the nasal septum
petrous ridge
petrous portion of the temporal bone that forms a large, triangular ridge in the floor of the cranial cavity, separating the middle and posterior cranial fossae; houses the middle and inner ear structures
posterior (dorsal) sacral foramen
one of the series of paired openings located on the posterior (dorsal) side of the sacrum
posterior arch
posterior portion of the ring-like C1 (atlas) vertebra
posterior cranial fossa
deepest and most posterior cranial fossa; extends from the petrous ridge to the occipital bone
posterior longitudinal ligament
ligament that runs the length of the vertebral column, uniting the posterior sides of the vertebral bodies
primary curve
anteriorly concave curvatures of the thoracic and sacrococcygeal regions that are retained from the original fetal curvature of the vertebral column
pterion
H-shaped suture junction region that unites the frontal, parietal, temporal, and sphenoid bones on the lateral side of the skull
ramus of the mandible
vertical portion of the mandible
ribs
thin, curved bones of the chest wall
sacral canal
bony tunnel that runs through the sacrum
sacral foramina
series of paired openings for nerve exit located on both the anterior (ventral) and posterior (dorsal) aspects of the sacrum
sacral hiatus
inferior opening and termination of the sacral canal
sacral promontory
anterior lip of the base (superior end) of the sacrum
sacrococcygeal curve
anteriorly concave curvature formed by the sacrum and coccyx; a primary curve of the vertebral column
sacrum
single bone located near the inferior end of the adult vertebral column that is formed by the fusion of five sacral vertebrae; forms the posterior portion of the pelvis
sagittal suture
joint that unites the right and left parietal bones at the midline along the top of the skull
sclerotome
medial portion of a somite consisting of mesenchyme tissue that will give rise to bone, cartilage, and fibrous connective tissues
scoliosis
abnormal lateral curvature of the vertebral column
secondary curve
posteriorly concave curvatures of the cervical and lumbar regions of the vertebral column that develop after the time of birth
sella turcica
elevated area of sphenoid bone located at midline of the middle cranial fossa
septal cartilage
flat cartilage structure that forms the anterior portion of the nasal septum
skeleton
bones of the body
skull
bony structure that forms the head, face, and jaws, and protects the brain; consists of 22 bones
somite
one of the paired, repeating blocks of tissue located on either side of the notochord in the early embryo
sphenoid bone
unpaired bone that forms the central base of skull
sphenoid sinus
air-filled space located within the sphenoid bone; most posterior of the paranasal sinuses
spinous process
unpaired bony process that extends posteriorly from the vertebral arch of a vertebra
squamous suture
joint that unites the parietal bone to the squamous portion of the temporal bone on the lateral side of the skull
sternal angle
junction line between manubrium and body of the sternum and the site for attachment of the second rib to the sternum
sternum
flattened bone located at the center of the anterior chest
styloid process
downward projecting, elongated bony process located on the inferior aspect of the skull
stylomastoid foramen
opening located on inferior skull, between the styloid process and mastoid process
superior articular process of the sacrum
paired processes that extend upward from the sacrum to articulate (join) with the inferior articular processes from the L5 vertebra
superior articular process
bony process that extends upward from the vertebral arch of a vertebra that articulates with the inferior articular process of the next higher vertebra
superior nasal concha
smallest and most superiorly located of the nasal conchae; formed by the ethmoid bone
superior nuchal line
paired bony lines on the posterior skull that extend laterally from the external occipital protuberance
superior orbital fissure
irregularly shaped opening between the middle cranial fossa and the posterior orbit
supraorbital foramen
opening located on anterior skull, at the superior margin of the orbit
supraorbital margin
superior margin of the orbit
supraspinous ligament
ligament that interconnects the spinous processes of the thoracic and lumbar vertebrae
suture
junction line at which adjacent bones of the skull are united by fibrous connective tissue
temporal bone
paired bones that form the lateral, inferior portions of the skull, with squamous, mastoid, and petrous portions
temporal fossa
shallow space on the lateral side of the skull, above the level of the zygomatic arch
temporal process of the zygomatic bone
short extension from the zygomatic bone that forms the anterior portion of the zygomatic arch
thoracic cage
consists of 12 pairs of ribs and sternum
thoracic curve
anteriorly concave curvature of the thoracic vertebral column region; a primary curve of the vertebral column
thoracic vertebrae
twelve vertebrae numbered as T1–T12 that are located in the thoracic region (upper back) of the vertebral column
transverse foramen
opening found only in the transverse processes of cervical vertebrae
transverse process
paired bony processes that extends laterally from the vertebral arch of a vertebra
true ribs
vertebrosternal ribs 1–7 that attach via their costal cartilage directly to the sternum
tubercle of the rib
small bump on the posterior side of a rib for articulation with the transverse process of a thoracic vertebra
vertebral (spinal) canal
bony passageway within the vertebral column for the spinal cord that is formed by the series of individual vertebral foramina
vertebral arch
bony arch formed by the posterior portion of each vertebra that surrounds and protects the spinal cord
vertebral column
entire sequence of bones that extend from the skull to the tailbone
vertebral foramen
opening associated with each vertebra defined by the vertebral arch that provides passage for the spinal cord
vertebra
individual bone in the neck and back regions of the vertebral column
vomer bone
unpaired bone that forms the inferior and posterior portions of the nasal septum
xiphoid process
small process that forms the inferior tip of the sternum
zygomatic arch
elongated, free-standing arch on the lateral skull, formed anteriorly by the temporal process of the zygomatic bone and posteriorly by the zygomatic process of the temporal bone
zygomatic bone
cheekbone; paired bones that contribute to the lateral orbit and anterior zygomatic arch
zygomatic process of the temporal bone
extension from the temporal bone that forms the posterior portion of the zygomatic arch