A&P Chapter 7 - The Axial Skeleton (lecture notes)

What are important regions/markings of the hyoid bone?

-body- attaches muscles of the larynx, pharynx, and tongue -greater horns- support larynx, attach muscles of the tongue -lesser horns-attach stylohyoid ligaments, support hyoid and larynx

What are the functions of sinuses?

-decrease weight of the skull -to be lined with mucus membranes, which produce mucus to moisten and clean the air -to serve as resonating chambers in speech production

Name some regions/markings of the occipital bone.

-external occipital protuberance -external occipital crest -occipital condyles -inferior and superior nuchal lines

What are the surface bones of the skull and what do they do?

-occipital bone, temporal bones, parietal bones, frontal bones, nasal bones, zygomatic bones, maxilla, and mandible -the surface bones protect the brain and sensory organs and serve as attachment sites for the neck

What makes up the axial skeleton?

-skull, vertebral calumn, and rib cage -in other words: the bones of the head and trunk that form the longitudinal axis of the body

What are the functions of the axial skeleton?

-support and protect organs of the body cavities -provide points of attachment for muscles that adjust positions of the head, neck, and trunk; perfroms breathing movements; and stabilize parts of the appendicular skeleton

What are the general functions of maxillae?

-support upper teeth -form inferior orbital rims -form lateral margins of external nares -form upper jaw and most of hard palate -contain maxillary sinuses (largest sinuses)

What are the purposes of the five deeper facial bones?

-to help separate oral and nasal cavities -to increase surface area in the nasal cavities -to help form the nasal septum -overall, the deeper facial bones form cavities

What are the joints of the parietal bones?

-with each other -occipital -temporal -frontal -sphenoid

How many thoracic vertebrae are there?

12 (T1-T12)

Describe ribs.

12 pairs of long, curved, flat bones that extend from thoracic vertebrae

How many facial bones are there and what is their purpose?

14; they protect and support entrances to the digestive and respiratory tracts

The sternal body articulates with the cartilage of which rib pairs?

2-7

How many bones are in the vertebral column?

26 - 24 vertebrae, the sacrum, and the coccyx

The mature coccyx consists of how many fused coccygeal vertebrae?

3 to 5

The developing sternal body consists of how many fused bones?

4 (fusion not complete till age 25; it leaves transverse lines)

The cranial sutures begin to form at what age?

5

The adult sacrum consists of how many fused vertebrae?

5; fusion finishes between ages 25 and 30

How many vertebrae are in the cervical region?

7

The skull has how many cranial bones?

8

How many bones make up the axial skeleton?

80

Describe the hypoglossal canal.

A foramen in the occipital bone; canals for hypoglossal nerves; a canal seen from a mid-sagittal view of the occipital bone that goes through the bone horizontally from the back of the head to the face

Describe the supra-orbital notch.

An incomplete supra-orbital foramen; medial

Which vertebra does not have a spinous process?

C1

Which vertebrae has the largest vertebral foramen?

C1, the atlas; its vertebral foramen has an anterior and posterior arch

The spinous process is replaced by an anterior arch in which vertebrae?

C1; the atlas (the posterior arch is on the oppsoite side of the large vertebral foramina)

Describe the atlas.

C1; top cervical verterae; articulates with occipital condyles of the skull; has no body or spinous process; has a large vertebral foramen with anterior and posterior arches

Describe the axis.

C2; second cervical vertebra; has a dens that pivots with the atlas, allowing us to shake our head no; has a heavy spinous process to attach muscles of head and neck

Describe the vertebra prominens.

C7; last (lowest) cervical vertebrae; transitions to thoracic vertebra; has long spinous process with broad tibercle; has large transverse process

Compare T12 to L1

T12 resembles L1 but has a facet for rib articulation

What is cleft palate?

a congenital fissure in the midline of the palat

Describe the hypophyseal fossa.

a depression within the sella turcica of the sphenoid that houses the pituitary

Describe the thoracic curve.

a primary curve that provides room for the thoracic organs

Describe the sacral curve.

a primary curve that provides rooms for various abdominopelvic organs

Describe the mastoid process of the temporal bone.

a process that juts out from the posterior, lateral portion of the bone; for muscle attachment; contains mastoid cells that connect to the middle ear cavity; located behind the ear

What is the median sacral crest?

a ridge formed from fusion of spinous processes; four pairs of sacral foramina on either side

What is the sacral tuberosity?

a rough area at the top lateral sides of the sacrum that attaches ligaments of the sacro-iliac joint

Describe the lumbar curve

a secondary curve that balances the weight of the trunk over the lower limbs; develops with the ability to stand; forms around 1 year of age

Describe the external occipital protuberance.

a small bump on the midline at the inferior side of the occipital bone

What is the sacral ala?

a wing on either side of the base of the sacrum that attaches muscles

Describe articular processes.

a=lateral projections between laminae and pedicles of individual vertebrae

The mucus membrane of the paranasal sinuses responds to environmental stress by doing what?

accelerating production of mucus (does not create swirls in the sinuses)

Primary curves are also called what?

accomodation curves

When do secondary curves develop?

after birth

What are paranasal sinuses?

air-filled chambers connected to nasal cavities

What are sinuses?

air-filled chambers in the skull

Describe the head of ribs.

aka capitulum; at vertebral end of rib; has superior and inferior articular facets; interacts with a process of the spine

Descibe the vomer.

an elongated, plow-shaped bone that forms the inferior and posterior part of the nasal septum

What part of the atlas comes in contact with the dens?

anterior arch

What parts of the skull does the ethmoid form?

anteromedial floor of the cranium, roof of the nasal cavity, part of the nasal septum, and medial orbital walls

The pectoral girdles are part of which skeleton?

appendicular

The occipital condyles do what?

articulate with the first cervical vertrabra (atlas)

What do costal facets do?

articulate with the heads of ribs

Describe the anterior fontanelle.

at intersection of fronal, sagittal, and coronal suture; the "soft spot" on the top of the infant head

Describe the posterior fontanelle.

at junction of lambdoid and sagittal sutures (back of head)

Describe mastoid fontanelles.

at junction of squamous and lambdoid sutures (back sides of the skull)

Where are sphenoidal fontanelles found?

at the junction of the squamous and coronal sutures (front sides of head)

The metnal protuberance of the mandible does what?

attaches facial muscles

The external occipital crest is for what?

attachment of ligamentum nuchae (ligament of the neck)

The superior and inferior temporal lines are for what?

attachment of the temporalis muscle; they are small horizontal lines, the inferior one being lower

What does the sacrum attach?

axial skeleton to pelvic girdle AND broad muscles that move the thigh

What part of the orbit does the sphenoid contribute to?

back of the eye socket

Why does the most significant growth in the skull occur before 5 years of age?

because at 5, the brain stops growing and cranial sutures develop

When do primary spinal curves develop?

before birth

Where is the ethmoid bone located?

between the orbits

What are the foramen rotundum and foramen ovale for?

blood vessels and nerves of the face and jaws

The internal acoustic meatus contains what?

blood vessels and nerves of the inner ear; facial nerve

The foramen spinosum is for what?

blood vessels and neves of membranes; it is a small hole posterior to the foramen ovale; not visible from anterior view

What are the major regions/markings of the sphenoid bone?

body, sella turcica, hypophyseal fossa, spehnoidal sinuses, lesser wings, greater wings, and pterygoid processes

What important function is associated with the ribs?

breathing

How are vertebrae numbered?

by region from top to bottom

The mucus secreted by the nasal epithelium does all of the following except what? a. moisten the air b. cleanse the air c. make air flow easier d. warm the air

c. make air flow easier Mucus does not make air flow easier, it moistens air, cleans it, and warms it.

What is another name for the skullcap?

calvaria

The body of the sphenoid forms its what?

central axis

The only vertebrae that have transverse foramina in the transverese processes are what?

cervical

What are the vertebral regions? What are they determined by?

cervical - 7 vertebrae thoracic - 12 lumbar - 5 sacral coccygeal The vertebral regions are determined by structural characteristics of individual vertebrae.

Name the secondary curves.

cervical and lumbar (develop after birht and shift the body weight to permit upright posture)

Transverse foramina are unique to what?

cervical vertebrae

What are the spinal curves?

cervical, thoracic, lumbar, sacral

Secondary curves are also called what?

compenation curves

What is whiplash?

complete or partial dislocation of cervical vertebrae

What can be found on each ramus of the mandible?

condylar process, coronoid process, and the mandibular notch

What is a unique characteristic of thoracic vertebrae?

costa facets (also called demifacets); found on the posterior, lateral part of the body of the vertebrae; the transverse costal facets are also unique to thoracic vertebrae

The dorsolateral surfaces of thoracic vertebrae have what?

costal facets, which articulate with heads of ribs

Transverse processes of cervical vertebrae are fused to what?

costal processes

What two types of bones make up the skull?

cranial bones (8) and facial bones (14)

What projects superiorly from the ethmoid bone?

crista galli

The head of ribs articulate to what part of vertebrae?

demifacets

What are ligamentum nuchae?

elastic ligaments that extend from c7 to the skull

What are the joints of the inferior nasal concahe?

ethmoid, maxillae, palatine, lacrimal bones

What are the joints of the sphenoid?

every cranial bone except for the mandible: ethmoid, frontal, occipital, parietal, temporal, palatine, zygomatic, maxillae, and vomer

Thre growth of the cranium is usually associated with what?

expansion of the brain

Decsribe the perpindicular plate of the palatine bones

extends from the horizontal plate to the orbital process of the orbital floor

Ribs 8-12 are what?

false ribs

The skull is derived from what?

fibrous membrane

Ribs 11 and 12 are what?

floating ribs; they have no connection with the sternum and connect to the vertebrae and muscles of body wall

Describe the inferior orbital fissure.

for cranial nerves and blood vessels; formed by the sphenoid and the maxilla; visible from an anterior view of the orbit; lowest fissure of the orbit;

Name the regions/markings of the frontal bone.

forehead, supra-orbital margin, glabella, lacrimal fossa, and frontal sinuses

What are the general functions of the temporal bones?

form part of the lateral walls of the cranium and zygomatic arches; articulate with mandible (no other bones do); surround and protect the inner ear; attach muscles of the jaws and head

Describe the pterygoid processes of the sphenoid.

form pterygoid plates; attach muscles of the lower jaw and soft palate; the part that extends out of the bottom of the body; there are two pterygoid plates on each pterygoid process

What is the vertebral canal?

formed by vertebral foramina of successive vertebrae; encloses the spinal cord

What are the general functions of the frontal bone?

forms anterior part of the cranium and eye socket; contains frontal sinuses

Describe the horizontal plate of the palatine bones.

forms inferior part of them

Describe the supra-orbital foramen

found below the eyebrow on each side of the frontal bone; for blood vessels for the eyebrows, eyelids, and frontal sinuses; top middle part of the supra-orbital notch; the inferior-orbital foramina exists on the maxillae

What are costal processes?

found in cervical vertebrae fused to transverse processes; they encircle transverse foramina for vertebral arteries and veins

Describe the sphenoid sinuses.

found on either side of the body firectly inferior to and slightly anterior to the sella turcica

Where can the mandibular foramen be found?

from a medial view; below the mandibular notch; this is the entrance to the mandibular canal; for blood vessels and nerves of the lower teeth (this is where the dentists puts anesthetic)

Describe the foramen rotundum.

from the anterior view, it is the small hole right below the superior orbital fissure (visible when the sphenoid is alone but not from anterior view of the face); from a superior view it appears to come out from under the lesser wing

What are the bones of the nasal complex?

fronta, sphenoid, ethomoid, maxillae, lacrimal, inferior nasal conchae, and nasal bones

What are the seven bones of the orbital complex?

frontal maxilla lacrimal ethmoidal sphenoid palatine zygomatic

What are the joints of the ethmoid

frontal and sphenoid; maxiallae, nasal bones, lacrimal bones, palatine bones, and inferior nasal conchae and vomer (everythin in the center of the skull)

What are the joints of the maxillary bone?

frontal, ethmoid, each other, and with all other facial bones except for the mandible (that one only articulates with the temporal process of the zygomatic bone)

Name the paranasal sinuses.

frontal, ethmoid, sphenoid, and maxillary (from the top down)

What are the joints of the lacrimal bones?

frontal, maxila, ethmoid

What bones form the superior part of the nasal cavities?

frontal, sphenoid, and ethmoid

What are intervertebral foramina?

gaps between pedicles of adjacent vertebrae; for nerve connections to spinal cord

In addition to the superior and inferior temporal lines, the parietal bone also contains what marking?

grooves for passing of cranial vessels

What are foramina?

holes that serve as passageways for blood vessels and nerves

What are the regions of the palatine bones?

horizontal plate and perpindicular plate

The foramen lacerum contains what?

hyaline cartilage, small arteries, and auditory tube; it is the foramen that is formed by the sphenoid, temporal, and occipital bones

What are sutures?

immovable joints of the skull

Looking down at the skull, where does the ethmoid bone appear in relation to the sphenoid?

in front of it

Describe the frontal suture.

in infants it goes down the middle of the frontal bone from the coronal suture to the end of the frontal bone

The first seven ribs are true ribs. They connect to the sternum by what?

individual costal cartilages

The nasal complex consists of what bones?

inferior conchae, frontal, sphenoid, ethmoid, maxilla, and lacrimal bones

Where are the sphenoidal sinuses found

inferior to the sella turcica

What are the two projections that project inferiorly from the posterior part of a typical vertebra?

inferipr articular processes

Spinal nerves run to and from the spinal cord within what structure?

intervertebral foramina

Describe the condylar process

it articulates with the temporal bone at the tempromandibular joint

Describe the anterior nasal spine of the maxillary bone.

it attaches the anterior nasal septum; anterior medial part of the maxilla (right in the front middle)

Describe the coronal suture.

it attaches the frontal bone to the parietal bones

Describe the sagittal suture

it extends from the coronal suture to the lambdoid suture between the parietal bones

Describe the perpindicular plate of the ethmoid bone.

it forms part of the nasal septum; inferior part of the ethmoid; it extends inferiorly from the cribriform plate

Describe the cribriform plate.

it forms the roof of the nasal cavity and part of the floor of the cranium; contains crista galli to attach to falx cerebri; loooking from an anterior view, the cribriform plate is the part that goes straight back; the crista galli extends up from the cribriform plate and the perpindicular plate extends down from it

Where is the prechiasmatic sulcus located in relation to the sela turcica of the sphenoid?

it is anterior to the sella turcica

Describe the zygomatic process of the temporal bone

it is inferior to the squamous part; it articultaes with the temporal process of the zygomatic bone to form the zygomatic arch; it forms part of the cheek bone

Describe the ramus of the mandible/

it is the ascending angle of the mandible on either side (ascending towards the mandibular notch; located right below the mandibular notch)

Describe the coronoid process of the mandible.

it is the insertion point for the temporalis muscle (which closes the jaws); it is the sharper-looking process that is anterior to the head of the condylar process

What happens at the transverse costal process?

it is where the tubercle of the rib articulates with the transverse process of a vertebra

Describe the orbital rim of the maxillary bone/

it protects the eye and other strucutres; located at the top of the maxialla (forms bottom part of the rim

Decribe the lambdoid suture.

it separates the occipital and parieal bones; may contain sutural bones (wormian bones)

Describe the squamous sutures.

join temporal bones with parietal bones

What are the smallest face bones?

lacrimal bones

What are the four major sutures?

lambdoid, coronal, sagittal, and squamous

What are the regions between the transverse processes and spinous process of a typical vertabrae?

laminae

What are fontanelles?

large areas of fibrous connective tissue that cover the unfused sutures of the infant skull AND allow the skull to flex at birth (not protective)

Describe lumbar vertebrae.

largest; thick, oval bodies; no costal facets or transverse costal factes; triangular vertebral foramen; superior articular process face medially and inferior articular processes face laterally; have slender transverse proesses that project dorsolaterally; massive spinous processes for attachment of lower back muscles

The coccyx attaches what?

ligaments and constricting muscle of the anus

Maxillary sinuses do what?

lighten the bone

The clinical term for distortion of the lower back is what?

lordosis

What type of vertebrae are characterized by short, stumpy spinous processes and large bodies?

lumbar bodies

The sacrum is curved more in which gender?

males (less curved in females so that it does not get in the way of the birth canal)

What are the three parts of the sternum (from top down)

manubrium, body, xiphoid

The palate is part of the what?

maxilla

What are the bones of the nasal septum? (My Very Fine Nasal SEPtum)

maxilla vomer frontal nasal bones sphenoid ethmoid palatine

What are the bones of the medial wall of the orbit?

maxilla, lacrimal, ethmoid, and sphenoid

Name the facial bones.

maxillae (2) palatin(2) nasal (2) vomer inferior nasal conchae (2) zygomatic bones (2) lacrimal bones (2) mandible hyoid bone (this one is technically an associated bone; there are 14 facial bones in total)

What bones form the lateral walls of the nasal cavities?

maxillae, lacrimal bones, ethmoid, and inferior nasal conchae

What are the joints of the vomer?

maxillae, sphenoid, ethmoid, and palatine bones as well as cartilaginous part of the nasal septum

What are the joints of the zygomatic bones?

maxillae, sphenoid, ethmoid, frontal, temporal

What are the largest sinuses?

maxillary

Describe the infra-orbital foramen

middle of maxilla; for sensory nerve to the brain (via the foramen rotundum of the sphenoid); right under supra-orbital foramen of the frontal bone

What bones form the roof of the orbit?

mostly the frontal bone

The nine superficial bones are for what?

muscle attachment

The inferior and supererior nuchal lines are attachment sites for what on the occipital bone?

muscles and ligaments

Air flow in the nasal cavity is made turbulant by what?

nasal conchae

Name the cranial bones.

occipital frontal parietal temporal sphenoid ethmoid

What foramina exist in the ethmoid bone?

olfactory foramina; exist in the cribifrom for olfactory nerves

Where to T1-T18 articulate with ribs?

one pair articulates at the superior costal facet, the other at the inferior costal facet

T9-T11 articulate with what?

one pair of ribs

The passageway that allows the optic nerve to reach the eyeball for the sense of vision is the what?

optic canal

The optic canal (located in the sphenoid) is for the passage of what?

optic nerves; from a superior view, the optic canal appears to come out of the top of the lesser wings of the sphenoid (the foramen rotundum appears to come out from under the lesser wings)

What are intervertebral discs?

pads of fibrocartilage that separate adjacent vertebral bodies.

What are the joints of the occipital bone?

parietal bones, temporal bones, sphenoid, first cervical vertebra (atlas, C1)

What are the joints of the frontal bone?

parietal, sphenoid, ethmoid, nasal, lacrimal, maxillary, and zygomatic bone (NOT temporal bones!)

The ethmoid bone makes up what?

part of the cranial floor and the superior part of the nasal cavity

The palatine processes of the maxillae form what?

part of the hard palate; located anterior to the palatine bones

The perpindicular plate of the ethmoid bone forms what?

part of the nasal septum (superior part)

What are the regions between the transverse processes and the body of a typical vertebrae?

pedicles

The intervertebral foramina _________.

permit the passage of nerves to and from the spinal cord

Describe spinous processes.

posterior projections of vertebrae; project from where vertibral laminae fuse

Describe transverse process of vertebrae.

projections from where laminae joint pedicles

What are the functions of the vertebral column?

protects the spinal cord, supports the head and body, attaches to skeletal muscles of the back

What part of the sphenoid attaches muscle of the lower jaw?

pterygoid plates

What does the sacrum protect?

reproductive, urinary, and digestive organs

Which of the ribs are referred to as vertebral ribs?

rib pairs 11 and 12 (their only articulation is to the vertenral column in the posterior part of the thoracic cage, no anterior articulation)

What is the lateral sacral crest?

ridge formed from transverse processes that were fused; attachest muscles of lower back and hip

What is the sacral cornua?

ridges formed from laminae of fifth sacral vertebra; lamina do NOT meet in the middle

Describe the cervical cuurve.

secondary curve; develops as infant learns to balance the weight of the head

The body of the sphenoid houses what structure, which holds the pituitary?

sella turcica

Describe the neck of ribs

short area betweeen head and tubercle

Describe the mandibular fossa of the temporal bone.

site of articulation with the mandible; at the site of attachment of zygomatic process

Describe characteristics of cervical vertebrae?

small body (only support the head); large vertebral foramen; concave superior surface; anterior edge is inferior to the posteror edge; transverse processes are fused to costal processes

Describe the tuburcle of ribs

small dorsal elevation that has an articular facet that contact the transverse process of thoracic vertebrae

Describe the xiphoid process.

smallest part of the sternum; attaches to sternal body AND diaphragm and rectus abdominis muscle

The sinuses, or internal chambers of the skull, are found in what bones?

sphenoid, ethmoid, frontal, maxillary

What are the main types of fontanelles?

sphenoid, mastoid, anterior, and posterior

What are the joints of the temporal bones?

sphenoid, parietal, occipital, zygomatic, and mandible (the temporal and frontal bones do not articulate; they are separated by the sphenoid)

The more straight end of the rib is what end? Where does it articulate?

sternal end; articulates with the costal cartilage of the rib cage

The petrous part of the temporal bone encloses what?

structures of the internal ear

What are the joints of the hyoid bone?

styloid ligaments connect the lesser horns to styloid processes of temporal bones (no connection to any other bones)

The superior surface of the atlas has what?

superior articular factes; they move towards each other on the superior side and are more flat on the inferior side

What are the small flat projections on the superior, posterior part of a typical vertebrae?

superior articular processes

Describe the manumbrium

superior portion of the sternum; broad triangular shape; articulates with clavicles; articulates with cartilages of first rib pair; has jugular notch

What are the general functions of the hyoid bone?

support the larynx; attach muscles of the larynx, pharynx, and tongue

The alveolar process of the mandible does what?

supports the lower teeth

Name the foramina of the frontal bone.

supra-orbital fissure and supra-orbital notch

What is the important marking of the zygomatic bone?

temporal process - meets the zygomatic process of the temporal bone

The styloid process of the temporal bone attaches what?

tendons and ligaments of the hyoid, tongue, and pharynx

What bones make up the vertebral column?

the 24 vertebrae, sacrum, and coccyx

The sphenoid bone forms what part of the cranium?

the anteiror base (it is shaped like a butterfly and the wings form a portion of the orbit)

The dens articulates with what part of the atlas?

the anterior arch

The lacrimal bones make up what?

the anterior portion of the medial wall of each orbit

The bones that support the limbs make up what?

the appendicular skeleton

Describe the foramen magnum.

the biggest hole in the occipital bone; connets the cranial cavity with the vertebral canal

What part of the mandible makes up the horizontal portion of the bone?

the body

What is the base of the sacrum?

the broad superior surface

The carotid canal is for what?

the carotid artery; passes through the temporal bone

What region of the spinal cord has the largest vertebral foramen?

the cervical region

What's the most flexible region of the back?

the cervical region

The manubrium articulates with what?

the clavicles and the cartilage of the first rib pair

What part of the mandible articulates with the temporal bone?

the condylar process (the head of it; the head has an articular surface for the tempromandibular joint)

What do the cranial bones enclose?

the cranial cavity, which contains the brain

What extends laterally from the crista galli of the ethmoid bone?

the cribriform plate - a perforated structure through witch olfactory nerves pass

What are some important regions/markings on the ethmoid bone?

the cribriform plate, the ethmoidal labyrinth, and the perpindicular plate

The bodies of the atlas and axis fuse during development to form what?

the dens

What is the most anterior part of the cranium?

the ethmoid

The ridge in the middle of the occipital bone seen from the inferior view is called what?

the external occipital protuberance

Describe the external acoustic meatus.

the external opening of the auditory canal; it ends at the tympanic membrane; air in there conducts sound to the eardrum; inferior to the squamous part of the temporal bone

The stylomastoid foramen is for what?

the facial nerve; it is the very small hole found between the styloid and mastoid processes

What is the sternum?

the flat bone in anterior midline of the thoracic wall

What part of the orbit does the palatine contribute to?

the floor

Describe the jugular foramen.

the foramen in the occipital bone for internal jugular vein; from an inferior view, it appears to be made by the occipital bone and the tempral bone; the jugular foramen are just lateral the occipital condylesand are bigger than the carotid canals observed in the temporal bone

After a sensory nerve passes through the infra-orbital foramen, where does it go?

the foramen rotundum of the sphenoid

What are the bones associated with the skull?

the hyoid and 6 auditory ossicles

The styloid processes of the temporal bones articulate to what bone?

the hyoid bone

What form the notch for the articulation of the head of the rib with the thoracic vertebrae?

the inferior costal facet along with the superior costal facet

The vomer is what part of the nasal septum?

the inferior part

What are the foramina of the maxillae?

the infra-orbital foramen and the inferior orbital fissure

The nasolacrimal canal protects what?

the lacrimal sac and the nasolacrimal duct

What is an important marking of the lacrimal bones?

the lacrimal sulcus, which is the location of the lacrimal sac and leads to nasolacrimal canal

What part of the orbit does the zygomatic bone contribute to?

the lateral wall

What is the only bone of the skull that does not articulate with others through a suture?

the mandible

What are the joints of the mandible?

the mandibular fossa of the temporal ones

The condylar process and coronoid process of the mandible are separated by what?

the mandibular notch

What is the main bone that forms the floor of the orbit?

the maxilla

What bones form the bridge of the nose?

the maxillae and nasal bones

What part of the orbit does the ethmoid contribute to?

the medial wall (and orbital rim)

The maxilla forms what part of the orbit?

the medial wall, floor, and rim

What are the foramina of the mandible?

the mental foramina and the mandibular foramina

What is the suture of the frontal bone called?

the metopic or frontal suture (it is found in the middle top part of the forehard)

The myohyloid line is for insertion of what?

the myohyloid muscle

What is the apex of the sacrum?

the narrow INFERIOR portion that articulates with the coccyx

The superior articular processes of the atlas articulate with what?

the occipital condyles of the skull - this articulation produces a gliding movement that allows us to nod our head "yes"

What is the sacral hiatus?

the opening at the inferior end of the sacral canal; bordered by sacral cornua; covered by connective tissues

What happens at the prechiasmatic sulcus of the sphenoid?

the optic nerve crosses over (the prechiasmatic sulcus is an optic groove)

Describe the squamous part of the tempral bone.

the part of the temporal bone that borders the squamous suture

Describe the tubular body

the part that glides around to the front; attaches muscles of pectoral girdle and trun; attacjest intercostal muscles htat move the ribs

Decsribe the alveolar process of the maxillae

the part that supports the upper teeth (part of maxilla where the upper teeth are)

What is the sacral canal?

the passageway that extends the length of the sacrum; contains nerves and membranes

What allows us to shake our head no?

the pivot joint between the anterior arch of the atlas and the dens of the axis

The vertebral ach forms what part of each vertebral foramen?

the posterior margin of it

The palatine bones form what?

the posterior third of the hard palate, part of the nasal cavity, and a portion of the orbit

What is the sacral promontory?

the prominent buldge at the anterior tip of the base

What is the coccygeal cornu?

the prominent lamina of the first coccygeal vertebrae

What form the rib cage?

the ribs and sternum

Laminae form what part of the vertebral arches?

the roof

L5 articulates with what?

the sacrum (which articulates with the coccyx)

Describe the sella turcica.

the saddle-shaped enclosure within the body of the sphenoid; superior surface of sphenoid; contains the hypophyseal fossa

What is the jugular notch of the manubrium?

the shallow indentation between clavicular articulations

What bones form the back of the eye socket?

the sphenoid and palatine bones

Compare the spinous processes of lumbar vertebrae and thoracic vertebrae.

the spinous processes of thoracic vertebrae point down; that of lumbar vertebrae point straight back

What bones make up the thoracic cage?

the sternum and the 24 ribs

What are the structures on each side of the dens of the axis?

the superior articular facets

What is the auricular surface of the sacrum?

the thick, flattened area at the top of the sacrum that articulates with the pelvic girdle to form the sacro-iliac joint

Describe the sternal body.

the tongue shaped part that attaches to the manubrium; attaches costal cartialges for ribs 2-7; transverse lines where fusion occurs

The tubercle contacts what?

the transverse costal facets of the transverse processes of the thoracic vertebrae

What seems to hold the dens in place?

the transverse ligament

What encloses the spinal cord?

the vertebral canal

What is formed by vertebral foramina of successive vertebrae?

the vertebral canal

What parts of the skeleton help us maintain that upright body position?

the vertebral column

What is posterior to the dens?

the vertebral foramen (axis)

What part of the sternum is last to ossify?

the xiphoid process (because of this it is most easily broken)

What is the important foramina of the zygomatic bone?

the zygpmaticofacial foramen, which is for a sensory nerve of the cheek

Describe the foramina of the palatine bones.

there are many in the lateral portion of the horizontal plate for small blood vessels and nerves of the mouth

Describe the superior and inferior articular processes of vertebrae.

they are for articulation with neighboring vertebrae; have articular facets

Describe the bodies of thoracic vertebrae.

they are heart-shaped and larger than the bodies of cervical vertebrae

The structures of the internal ear are house in the ______ of the ______.

they are housed in the petrous part of the temporal bone

Describe the inferior processes of the atlas

they are more flat

Describe the spinous processes of cervical vertebrae.

they are notched, aka bifid

Describe the spinous process of lumbar vertebrae.

they are squared off and resemble an ax

Where can the mental foramina be found? What are they for?

they can be found anteriorly, on either side of the mental protuberance; they are for sensory nerves of the lips and chin

Describe the ethmoidal labyrinths

they consists of ethmoidal cells (air-filled cavities); consist of superior and middle nasal conachae (only middle nasal concahe visible from anterior view of an articualted skull); includes each wing-looking structure of the ethmoid

Describe rib pairs 1-10.

they contact costal and transverse costal facets of thoracic vertebrae

Describe the lesser wings of the sphenoid.

they extend horizontally anterior to the sella turcica (seem to be superior to the greater wings)

Describe the greater wings of the sphenoid.

they extend laterally form the body and form part of the cranial floor and the posterior part of the orbit; the sphenoidal spine lies at the corner of each greater wing

Describe the superior articular facets of the atlas.

they face each other (medially)

Describe the inferior articular processes of lumbra vertebrae

they face laterally

Describe the superior articular processes of lumbar vertebrae

they face medially

Describe vertebral arches.

they form the posterior margin of vertebral foramen; have wells called pedicles; have laminae, which form the roof of the vertebral arch

Describe T1-T10

they have thick transverse processes with thick transcerse costal facets for rib articulation.

What do paranasal sinuses do?

they lighten the skull bones and contain mucus epithelium (release mucus into the nasal cavities)

Describe vertebral bodies.

they transfer weight along the spine; they form anterior margin of the verterbal foramen (front part of spine)

Kyphosis is associated with distortion in what curve?

thoracic

The spinous processes are especially long on which type of vertebrae?

thoracic

Name the primary curves.

thoracic and sacral

Describe the vertebral foramina and spinous processes of thoracic vertebrae.

thoracic vertebrae have relatively smaller vertebral foramina than cervical vertebrae and longer, more slender spinous processes than cervical vertebrae

The thoracic cage consists of what?

thoracic vertebrae, ribs, sternum, and costal cartilages

What are the auditory ossicles (of the temporal bone)?

three tiny bones in the tympanic cavity (middle ear); they transfer sound vibrations from the tympanic membrane (eardrum) to the inner ear

What is the function of the intervertebral foramina?

to connect spinal nerves to the spinal cord

What are the general functions of the zygomatic bones?

to contribute to the rims and lateral walls of the orbits; toform parts of zygomatic arches

What are the general functions of the sphenoid bone?

to form part of the floor of the cranium, to unite the cranial and frontal bones, and to strengthen the side of the skull; the sphenoid bone contains sphenoidal sinuses

What are the general functions of the palatine bones?

to form posterior poriton of the hard palate and contribute to the floors of the orbit

What are general functions of the mandible?

to form te lower jaw

What are the general functions of the ethmoid bone?

to form the anteromedial floor of the cranium, to form the roof of the nasal cavity, to form part of the nasal septum and medial orbital wall, to contain ethmoidal cells

What are the general functions of the vomer?

to form the inferior part of the bony nasal septum

What are the general functions of the lacrimal bones?

to form the medial walls of the orbits

What are the general functions of the occipital bone?

to form the posterior and ifnerior surfaces of the cranium

What are the general functions of the parietal bones?

to form the superior and lateral surfaces of the cranium

What are the functions of the thoracic cage?

to protect oragns of the thoracic cavity (heart, lungs, thymus) AND provide attachment for muscles involved in breathing, maintaining position of the vertebral column, and moving pectoral girdles

What are the general functions of the inferior nasal conchae?

to slow inhaled air, create air turbulance, increase epithelial surface, and warm and humidify inhaled air in the nasal cavity

What are the general functions of the nasal bones?

to support the bridge of the nose and connect to cartilages of distal portions of the nose that extend to external nares

T10-T12 do what?

transition to lumbar vertebrae

What are the openings in the transverse processes?

transverse foramina

Fused sacral bones leave behind what?

transverse lines

The first two coccygeal vertebrae have what?

transverse processes and unfused vertebral arches

What projects out on a transverse plane from the atlas?

transverse proesses (they are wide and short)

What are the two types of ribs

true ribs and false ribs

Ribs 1-7 are what?

true ribs; vertebrosternal rubs that connect to the sternum via costal cartilages

What part of the rib articulates with transverse processes of thoracic vertebrae?

tubercles

Describe the bones of the infant skull.

two frontal bones, four occipital bones, and several sphenoid and ethmoidal elements; fusion is not complete at birth

T1-T18 articulate with what?

two pairs of ribs

Cleft lip is an incomplete fusion of what?

upper jaw components of a developing embryo

Each vertebra consists of three main parts. Name them.

vertebral body vertebral arch articular process

The structure that encloses and protects the spinal cord is the what?

vertebral canal (NOT the intervertebral foramen)

Compare the vertebral prominens and T1.

vertebral prominens, C7, resembles T but lacks facets for rib articulation

Rib pairs 8, 9, and 10 are called what?

vertebrochondral ribs

What are the two types of false ribs

vertebrochondral ribs (8-10) and floating ribs (11-12)

Ribs 8-10 are what?

vertebrochondral ribs; their costal cartilages fuse together and merge with the cartilages of rib pair seven before reaching the sternum

What is the difference between vertebrosternal ribs and vertebrochondral ribs?

vertebrosternal ribs connect directly to the sternum wheras vertebrochondral ribs do not

What are the joints of the nasal bones?

with each other, ethmoid, frontal, and maxillae

What are the joints of the palatine bones?

with each other, maxillae, sphenoid, ethmoid, inferior nasal conchae, and vomer