89 terms

Anatomy Midterm; Chapter 7 Axial Skeleton

Axial skeleton
80 bones, supports and protects, muscle attachment for: movement of head/neck/trunk, respiration, stabilize and position the appendicular skeleton
Cranial Bones
8 bones
Facial bones
14 bones of the skull which protect and support the eyes, ears, nose and mouth
Thoracic cage
consists of thoracic vertebrae, the ribs and the sternum; protects the heart, lungs, thymus and other structures within the cavity; serves as an attachment site for muscles involved in respiration, positioning vertebral column, movements of the pectoral girdle and upper limb
the bony structure units of the spinal column (26)
lower posterior region of the head/skull
occipital condyles
projections of the occipital bone that articulate with lateral masses of the first cervical vertebra
foramen magnum
large opening in occipital bone that allows spinal cord to attach to brain
occipital protuberance
a bump that extends out from the occipital bone
the two bones forming the sidewalls and roof of the cranium, lat. superior skull
superior anterior skull, forms roof of orbits
lacrimal fossa
fossa of the frontal bone that contains the lacrimal gland, located just inside the lateral portion of the supraorbital ridge.
inferior lateral skull (temples)
external acoustic canal
ear hole
mastoid process
part of the temporal bone that attaches to some of the muscles of the neck
zygomatic process
part of the temporal bone that forms part of the posterior cheekbone
styloid process
sharp (needle-like) projection from the bottom of the temporal bone
suture that separates occipital from parietal
Suture across top front, between frontal and parietal
suture b/t parietal bones
suture that separates parietal and temporal
butterfly-shaped bone at the base of the skull, articulates with the 7 other cranial bones, most central cranial bone, post. walls of orbits and ant. floor of cranium
sella turcica
bony process on sup. center of sphenoid bone
hypophyseal fossa
"seat of the saddle" part of the sella turcica, holds the Pituitary gland
lesser wings
sphenoid; bat-shaped portions of the spheniod anterior to the sella turcica
greater wings
portions of the sphenoid seen exteriorly anterior to the temporal and forming a part of the eye orbits
optic canals
openings in the bases of the lesser wings through which the optic nerves enter the orbits to serve the eyes
anterior to sphenoid, forms medial wall of orbits, roof of nasal cavity + part of nasal septum
cribriform plate
part of the ethmoid bone that forms the roof of the nasal cavity found in the anterior floor of the cranium
olfactory foramina
openings for olfactory nerves
perpendicular plate
forms the superior part of the nasal septum
superior nasal conchae
scroll shaped projections on the lateral walls of the nasal cavity; they increase vascular & mucus membrane surface area in the nasal cavities, which aids in the snese of smell, and warm, moisten and filter incoming air
middle nasal conchae
scroll-like projection on each lateral wall of nasal cavity
largest facial bones, form upper jaw/ supports upper teeth, forms inferior orbits + hard palate
infraorbital foramen
sensory nerve to face
palatine process
forms the anterior portion of the hard palate (roof) of the mouth also forms parts of the nasal cavity and eye orbits
posterior hard palate
forms the inferior portion of the nasal septum, articulates w/ perpendicular palate
zygomatic bone
cheek bone, lateral walls of orbits
temporal process
Articulates with zygomatic process of the temporal bone to form the zygomatic arch
form the bridge of the nose, attachment site for cartilage of nose
smallest facial bones, form medial walls of orbits
lacrimal sulcus
A groove along the anterior lateral surface of the lacrimal bone
lower jaw bone
mandible body
Main part of the jaw bone, horizontal part, holds lower teeth
mandible ramus
verticle part of jaw.
condylar process
the posterior upward projection of the ramus that fits into the temporomandibular joint, which is the hinge of the mandible
coronoid process
the anterior, non-articulating process of the ramus of the mandible which serves as the insertion for the temporalis muscle.
paranasal sinuses
air cavities within the cranial bones that open into the nasal cavities, lighten skull bones, acts as resonating chambers for voice, produce mucus, wash debris into nasal cavity, prevent debris from entering nasal tract
Maxillary, Frontal, Sphenoid, Ethmoidal
4 types of paranasal sinuses
Vertebral Column
26 bones, support head, limbs and trunk, support upper organs, transfers body weight to lower limbs, protects spinal cord
'neck', 7 vertebrae, C1-C7, supports skull, most flexible region, smallest lightest vertebrae,large vertebral foramen, all have 2 transverse foramen, to support artery
superior back, 12 vertebrae, T1-T12, supports thoracic cage, very little flexibility, larger, thicker bodies, smaller vertebral foramen, inferiorly angled spinous processes, each vertebrae articulates w/ a pair of ribs
inferior back, 5 vertebrae, L1-L5, supports abdominal regions, more flexible than thoracic spine, large oval bodies, small triangular vertebral foramen,very large, short spinous processes
base of spine, 5 fused vertebrae, S1-S5, transfers upper body weight to lower limbs
tail bone, 3-5 fused vertebrae, Co1-Co3-5)
Primary Curves
c curve of spine, during infancy
secondary curves
cervical and lumbar curves after several months, allows for upright posture and even distribution of weight
lordotic curve
spine arches anteriorly, forms cervical and lumbar curves
kyphotic curve
spine arches posteriorly, forms thoracic and sacral spinal curves
part of vertebrae that is the main structure and most anterior part
vertebral arch
posterior part of vertebrae
vertebral foramen
surrounds the spinal cord, formed by body and vertebral arch
spinous process
posterior projection of vert. arch, site of muscle attachment
transverse process
lat. projection of vert. arch,site of muscle attachment
articular facets
articulations b/t vertebrae
no body or spinous process, extra large vertebral foramen (for brain stem), articulates w/ skull at the occipital condyles, forming the atlantoccipital joint , allows for 'yes'
contains dens process- vertical projection of the body, provides pivot for rotation of atlas, articulates w. atlas forming atlanaxial joint, allows for 'no'
ligamentum nuchae
long post. ligament, attaches all spinous process to externa occipital protuberance, provides large area for muscle attachment
intervertebral foramen
openings b/t adjoining vertebrae, allow spinal nerves to exit spinal cavity
intervertebral disc
fibrocartilage pads located b/t discs, cushion vertebrae +absorb shock
annulus fibrosis
outer layer of fribrocartilage of disc
nucleus pulposis
gelatinous inner core of disc
herniated disc
protrusion of a degenerated or fragmented intervertebral disk so that the nucleus pulposus protrudes, causing compression on the nerve root
triang. wedge, 5 vertebrae fused by 25-30 years old, attaches axial skeleton to appendicular skeleton
sup. edge of sacrum
inferior edge of sacrum
median sacral crest
ridge of the fused spinous processes of the sacral vertebrae
sacral canal
continuation of vertebral canal
sacral foramina
Allow the passage of sacral spinal nerves.
articular surface
lateral edge, articulates with pelvis, forms sacroilac joint
most inferior region of vertebral column, attachment site of muscle controlling anus
thoracic cage
consists of thoracic vertebrae, the ribs and the sternum; protects the heart, lungs, thymus and other structures within the cavity; serves as an attachment site for muscles involved in respiration, positioning vertebral column, movements of the pectoral girdle and upper limb
maniubrium (upper part), body, and xhypoid process (lower)+ all parts of the ____.
attachment site for many muscles
costal cartilages
cartilage connecting ribs to sternum
true ribs
direct connection to sternum (1-7)
false ribs
(8-12), indirectly connected to sternum,
floating ribs
11-12, no connection to sternum