Advertisement Upgrade to remove ads

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

Skull

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

Maxilla

upper jaw; anterior and inferior to zygomatic bone to which its joines;

Mandible

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.

skull

The bony structure of the head

cranium

the part of the skull that encloses the brain

sutures

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

glabella

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

mandible

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

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set