chapter 7 axial skeleton

Axial Skeleton

Axial Skeleton

Composed of the skull, hyoid, auditory ossicles vertebral columm, and thorax

articulates with temporal bone

Condyle (condylar process) articulates with?

what vertebrae has transverse foramen?

cervical

the head of the rib articulates with

inferior and superior demifacets

the tubercle of rib articulates with which of the following

costalfacet of transverse process

which vertebral curves are secondary

cervical and lumbar

which vertebral curves are primary

thoracic and sacral

which process of mandible is an insertion point of the temporalis muscle

coronoid process

how many bones make up axial skeleton

80

types of bones

flat bones, long bones, short bones, irregular bones, sesamoid bones, and sutural bones

sutural bones

Coronal sutures - Unites frontal bone and both parietal bones

Sagittal sutures - Unites two parietal bones

Lambdoid suture - Unites two parietal bones to occipital

Squamous sutures - Unite parietal and temporal bones

sagittal sutures

Unites two parietal bones

lambdoid suture

Unites two parietal bones to occipital

squamous sutures

Unite parietal and temporal bones

coronal sutures

Unites frontal bone and both parietal bones

sesamoid bones

develop in tendons where there is considerable friction & Tension, patella

irregular bones

vertebrae, facial bones, hip bones, calcaneus (heel)

short bones

carpals and tarsals

long bones

femur, tibia, fibula, humerus, ulna, radius, metacarpals, metatarsals, and phalanges

flat bones

cranial bones, ribs, sternum, scapulae, clavicles. (layer of spongy bone

Long Bones

Bones that are longer than they are wide; examples include femur, tibia, and humerus.

Short Bones

Bones that are approximately equal in length and width; examples include carpals and tarsals.

Flat Bones

Thin, flattened bones; examples include cranial bones, ribs, and sternum.

Irregular Bones

Bones with complex shapes; examples include vertebrae and facial bones.

Sesamoid Bones

Bones that develop in tendons due to friction and tension; an example is the patella.

Sutural Bones

Small extra bone plates located within the sutures of cranial bones.

Cranial Bones

8 bones that form the braincase, including frontal, parietal, temporal, occipital, sphenoid, and ethmoid bones.

Facial Bones

14 bones, mandible, maxilla, zygomatic, nasal, lacrimal, palatine, inferior nasal conchae, and vomer.

Foramen Magnum

A large opening in the occipital bone allowing the passage of the spinal cord.

deppressions and openings

     Allow the passage of blood vessels and nerves

     Form joints

processes

     Projections or outgrowths that form joints

     Serve as attachment points for ligaments and tendons

sulcus

groove,

condyle

round surface

crest

ridge

fossa

depression

process

prominence feature; projection of bone

fissure

hole oval in shape

foramen

hole circular in shape

tubercle

smooth

tuberosity

rough

facet

flat surface

8 cranial bones

parietal, occipital, temporal, frontal, sphenoid, ethmoid

facial bones

14; mandible(1), maxilla, zygomatic bone, nasal bones, lacrimal bones, palatine bones, inferior nasal conchae, vomer (1)

frontal structures

supra-orbital margin, supra- orbital foramen, frontal sinuses

parietal bones structures

form greater portion of the sides and roof of the cranial cavity

temporal bones structures

Temporal squama, zygomatic process

i. Mandibular fossa and articular tubercle articulate with mandible (condyle) to form temporomandibular joint (TMJ) (jaw joint)

ii. Mastoid portion, mastoid process, internal auditory meatus, styloid process, petrous portionk

temporomandibular joint (TMJ) (jaw joint)

Mandibular fossa and articular tubercle articulate with mandible (condyle) to form

occipital bone structures

foramen magnum, occipital condyles (Articulates with depressions of atlas (C1) – allows for dorso-ventral movement of head (up and down), external occipital protuberance (above foramen magnum)

sphenoid bone structures

(articulates with every bone) body, sella turcica, greater wings, lesser wings, pterygoid processes

ethmoid bone structures

cribriform plate, crista galli, perpendicular plate, superior nasal concha, middle nasal concha

what bones make up zygomatic arch

Formed by the zygomatic process of the temporal bone and the temporal process of the zygomatic bone.

Sphenoid Bone

A bone that unites cranial and facial bones, articulating with multiple other bones.

Joins anteriorly with frontal and ethmoid bones, laterally with temporal bones, and posteriorly with occipital bone

Ethmoid Bone

Located in the anterior part of the cranial floor, medial to the orbits.

Nasal Conchae functions

Structures that increase surface area in the nasal cavity, warming and humidifying inhaled air.

Mandible

The lower jawbone, consisting of various parts including the body , mental foramen, mandibular notch, condylar process, and ramus.

Nasal Septum components

vomer, perpendicular plate of ethmoid bone, and septal nasal cartilage.

Eye Orbit

Composed of 3 cranial bones (frontal, sphenoid, ethmoid) and 4 facial bones (palatine, zygomatic, lacrimal, maxilla).

Fontanels

Soft spots on an infant's skull that close at various ages, including anterior (18-24 months), posterior (2-3 months).Posterolateral fontanel (mastoid) closes 6-8 months after birth , & Anterolateral fontanel (sphenoidal) – 6 months after birth

Sutural Bones

Small bones located within cranial sutures, classified by location.

coronal sutures

Unites frontal bone and both parietal bones

sagittal sutures

Unites two parietal bones

lambdoid sutures

Unites two parietal bones to occipital

squamous sutures

Unite parietal and temporal bones

Hyoid Bone

A bone that supports the tongue and is not directly attached to other bones.

Paranasal Sinuses

Located in frontal, ethmoid, sphenoid, and maxillary bones, they help moisten and cleanse inhaled air & increase surface area.

Vertebral Column

Composed of 26 bones, including 7 cervical, 12 thoracic, and 5 lumbar vertebrae.

Spinal Curves

The cervical and lumbar curves are convex (secondary), while thoracic and sacral curves are concave (primary).

Costal Facets

21. Thoracic vertebrae can be distinguished from other vertebrae by presence of what structure

C1

the atlas (permits up and down movement), a

C2

the axis (permits side-to-side movement

What structure on the atlas and dens makes it different than any other cervical vertebrae

c2 has bifid spinous process and c1 has no spinous process

Coccyx Fuse at what age

around age 20-30,

at what age do the bones of the sacrum fuse

between 16-18; complete fusion at age 30

Thoracic Cage

Composed of 12 pairs of ribs( 7 pains of true ribs and 5 pairs of false ribs), sternum, costal cartilages, and 12 thoracic vertebrae.