7.6: Key Terms

Example and Directions

Words (or words that have the same definition)	The definition is case sensitive	(Optional) Image to display with the definition [Not displayed in Glossary, only in pop-up on pages]	(Optional) Caption for Image	(Optional) External or Internal Link	(Optional) Source for Definition
(Eg. "Genetic, Hereditary, DNA ...")	(Eg. "Relating to genes or heredity")		The infamous double helix	https://bio.libretexts.org/	CC-BY-SA; Delmar Larsen

Glossary Entries

Word(s)	Definition	Image	Caption	Link	Source
alveolar process of the mandible	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	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 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 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
vertebra	individual bone in the neck and back regions of the vertebral column
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
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