107 terms

The Skeleton

Axial Skeleton
Skull, mandible, hyoid, vertebtal column, thoracic (rib) cage, sternum, sacrum, coccyx. Forms uprite axis of body and protects brain, spinal cord, vital organs in thoracic region
Number of Bones Chart
average adult has 206 bones
or cranium; Protects the brain, supports organs of vision, hearing smell, taste, and provides foundation for structures taht take air, food and water into body.
Process & Other Fetures of Skull Chart
Superior View of Skull Bones
Contains 2 Parietal Bones, Frontal Bone, Saggital Suture and Corneal Suture; Parietal bones joined midline by Sagittal Suture and Parietal bones are connected to Frontal Bone by Corneal Suture
Posterior View of Skull
Parietal and Occipital bones, Lambdoid suture, Sutural Bones, External occipital protuberance, Ligamentum nuchae, Nuchal lines
Parietal & Occipital Bones
major structures of skull
Lambdoid Suture
between parietals and occipital bone
Sutrual bones
extra small bones that may be present form along lambdoid suture: variable
External Occipital Protuberance
on occipital bone and can be felt through scalp at base of head; site of attachment for Ligamentum Nuchae which helps keep head erect
Ligamentum Nachae
elastic ligament that extend down neck and helps keep head erect by pulling on occipital region of skull; attaches to external occipital protuberance
Nuchal Lines
set of small ridges that are neck muscle attachment points
Lateral View of Skull
Parietal bones, Squamous part of temporal bone, Squamous suture, Temperal Bone, Greater wing of sphenoid, Zygomatic bones, Maxilla, Mandible
Parietal Bones and Squamous Part of Temp. Bone
form most of side of skull
Squamous Suture
joins the parietal and temporal bone
Temporal Bone
has External auditory meatus, Mastoid process, Temporal lines, Zygomatic process of Zygomatic arch
External Auditory Meatus (Canal)
prominent feature of temporal bone - large hole surrounded by external ear
Mastoid Process
posterior and inferior to auditory canal - large inferior proection. Can be seen and felt as a prominent lump just posterior to the ear. Not solid bone and filled w/mastoid air cells which are connected to inner ear.
Temporal Lines
superior and inferior lines - attachment points of temporalis muscles, on of major muscles of mastication, arch across lateral surface of parietal bone
Greater Wing of Sphenoid
bone immediately anterior to the temporal bone - appears to be 2 bones, one on each side of skull, is actually single bone extending across skull
Zygomatic bones
or cheekbone which can be easily seen and felt on face; anterior to sphenoid bone - has temporal process of the zygomatic arch
Zygomatic Arch
consists of joined processes from temporal and zygomatic bones, forms bridge across side of skull. Easily felt on side of face, muscles on each side of arch can be felt as mandible opens and closes
upper jaw; anterior and inferior to zygomatic bone to which its joines;
lower jaw; inferior to maxilla and atriculates w/the temporal bone. consists of 2 main portions: body (extends anteroposteriorly) and ramus (extends superiorly from body toward temperal) w/condyle and coronoid processes
Mandible Body
extends anteroposteriorly
Mandible Ramus
(branch); extend superiorly from body towards temporal. Superior end has condyle and coronoid process
Mandibular Condyle
articualtes w/mandiblar fossa of the temporal bone
Mandibluar Corondoid Process
temporalis muscle, one of chewing muscles, attaches
Alveolar Process of Maxilla and Manible
of maxilla - contains superior (upper) teeth
of mandible - contains inferior (lower) teeth
Anterior View of Skull
Major structures are frontal bone (forehead), zygomatic bones (cheekbones), maxillae, and mandible. Maxilla and mandible bear teeth. Contain Orbits and Nasal cavities
Orbits of Skull
Cone-shaped fossae w/their apices oriented posteriorly. Provides protection for eyes and attachement points for muscles that move eyes. Contains Nasolacrimal canal and Optic canal
Nasolacrimal Canal
nasolacrimal ducts passes through from orbit into the nasal cavity, carrying tears from eyes to nasal cavity
Optic Canal
optic nerve for vision passes from eye through canal at posterior apex of orbit and enters cranial cavity
Oribit Bones chart
Bones of Nasal Cavity
Nasal cavity, Nasal septum (vomer, perpendicular plate of ethmoid), Nasal conchae (inferior, middle and supior)
Nasal Cavity
pear-shaped, open anteriorly
Nasal Septum
divides nasal cavity into right and left halves; bony part is vomer and perpendicular plate of ethmoid, Hyaline cartialge anterior part
Nasal Conchae
3 bony shelves that form lateral walls of nasal cavity; inferior nasal concha is seperate bone, and middle and superior nasal conchae are projections from ethmoid bone. increases surface of nasal cavity to faciliate moistening, removal of particles and warming of air inhaled
Paranasal Sinuses
large cavities within several bones of nasal cavity, Functions: decrease skull weight and act as resonating chambers, Named for bone in which they are found (frontal, maxillary, ethmoidal, sphenoidal)
Paranasal Sinuses Names
Named for bones in which they are found: Frontal, Maxillary, Ethmoidal, Sphenoidal
Skeleton/Skeletal System
composed of bones, cartilages, joints and ligaments; accounts for 20% of your body mass.
The bony structure of the head
the part of the skull that encloses the brain
immovable joints that unite cranial bones
frontal bone
the large cranial bone forming the front part of the cranium: the forehead and the upper part of the orbits
supraorbital margins
Mark the superior limits of the orbits, the bony recesses that support and protect the eyeballs
anterior cranial fossa
Part of the skull that accommodates the frontal lobe.
supraorbital foreman (notch)
Tiny hole above eyebrow that allows nerves to come through
The smooth area between the eyebrows just above the nose
frontal sinuses
located in the frontal bone just above the eyebrows
parietal bones
form most of the roof and upper sides of the cranium
coronal suture
between frontal and parietal bones
sagittal suture
where the parietal bones meet superiorly at the cranial midline
lambdoid suture
where parietal bones meet the occipital bone posteriorly
squamous suture
Joins the parietal bones to the temporal bones
occipital bone
forms the posterior floor and walls of the cranium
posterior cranial fossa
fossa primarily formed by the occipital bone, with contributions from the temporal and parietal bones
foramen magnum
the large opening at the base of the cranium through which the spinal cord passes
occipital condyles
Markings on the base of the Occipital Bone where the skull sits on the 1st vertebrae (atlas) of the neck
hypoglossal canal
opening medial and superior to the occipital condyle through which the cranial nerve passes (XII)
external occipital protuberance
median protrusion on occipital bone superior to foramen magnum
temporal bones
bone on the side of the head near the ears
squamous part
Lateral flat surface of temporal bone, inferior to squamous suture
zygomatic process
a slender process of the temporal bone that strengthens the zygomatic arch
zygomatic arch
the slender arch formed by the temporal process of the cheekbone that bridges to the zygomatic process of the temporal bone
mandibular fossa
the depression in the temporal bone into which the condyle of the mandible fits.
tympanic part
small, bony ring surrounding the entrance to the external acoustic meatus of temporal bone
external acoustic meatus
Canal leading to eardrum and middle ear
petrous part
Thick part of temporal bone, houses sensory structures of inner ear
middle cranial fossa
formed by part of the sphenoid bone and the temporal bone, supports the temporal lobes of the brain
jugular foramen
This foramen has one vessel and three nerves passing through it. It is found along the suture between the temporal and occipital bones.
carotid canal
anterior ofthe jugular foramen, transmits the internal carotid artery into the cranial cavity
foramen lacerum
jagged opening between the petrous temporal bone and the sphenoid providing passage for numerous small nerves
internal acoustic meatus
positioned superlateral to the jugular foramen transmits cranial nerves VII and VIII
mastoid process
process of the temporal bone behind the ear at the base of the skull, acts as an anchoring site for some neck muscles
styloid process
extends from the base of the temporal bone, attachment point for several tongue and neck muscles
stylomastoid foramen
between the styloid and the mastoid processes, allows cranial nerve VII (facial nerve) to leave the skull
mastoid air cells
full air cavities (sinuses) that is located in the mastoid process
sphenoid bone
the bat-shaped bone that extends behind the eyes and forms part of the base of the skull
sphenoidal sinuses
A paranasal sinus found in the body of the sphenoid
sella turcica
depression in the sphenoid bone where the pituitary gland is located
hypophyseal fossa
The Hypophyseal Fossa is "seat of the saddle" (Sella Turcica) part of the Sphenoid bone. It is the groove that is the deepest part of the body and it holds the Pituitary gland.
(Sphenoid Bone)
greater wings
portions of the sphenoid seen exteriorly anterior to the temporal and forming a part of the eye orbits
lesser wings
bat-shaped portions of the sphenoid anterior to the sella turcica
pterygoid processes
vertical projections that begin at the boundary between the greater and lesser wings of the sphenoid; serve as sites for attachment of muscles that move the mandible and soft palate
optic canals
Allow passage of the optic nerve (cranial nerve II) and the opthamalic arteries.
superior orbital fissure
fissure between the greater and lesser wings of the sphenoid bone that transmits structures from the cranial cavity to the orbit
foramen rotundum
1st of three holes from anterior, situated laterally of the sella turcica, most anterior hole. Medial part of the the greater wing and usually oval
foramen ovale
This foramen is found in the sphenoid bone on the middle fossa of the cranium. It is the first foramen that the mandibular nerve passes through as it leaves the cranium.
foramen spinosum
transmitts the middle meningeal artery which serves the internal faces of some cranial bones
ethmoid bone
form, forms part of the posterior portion of the nose, the orbit, and the floor of the cranium
cribriform plates
Found on each side of the crista galli and allows nerve fibers carrying nerve impulses from the olfactory receptors of the nose to reach the brain
crista galli
superior projection in the middle of the cribriform plate of the ethmoid bone
perpendicular plate
inferior projection of the ethmoid that forms the superior part of the nasal septum
lateral mass
Lateral to Perpendicular plate, riddled with Ethmoidal air cells.
ethmoidal air cells
sinuses- air pockets in area behind the nose and eyes
superior nasal conchae
thin, delicately coiled plates of bone extending medially from the lateral masses of the ethmoid into the nasal cavity
middle nasal conchae
higher projection, attached or connected to ethmoid bone. forms paired orbital plates with superior conchae
orbital plates
two smooth plate like structures which form the medial walls of the eye
sutural bones
tiny irregularly shaped bones that appear within sutures
Lower jaw bone
mandibular angle
posterior point at which ramus of mandible meets the body of mandible
mandibular notch
small indentation in the middle of the lower jawbone
coronoid process
the anterior, non-articulating process of the ramus of the mandible which serves as the insertion for the temporalis muscle.
condyler process
The articulation between the mandible and skull.
mandibular body
anchors the teeth
alveolar process
a ridge that forms the borders of the upper and lower jaws and contains the sockets of the teeth