The Axial Skeleton

Consists of structures found along the midline of the body

axial skeleton

Bones of the axial skeleton include

skull
hyoid
vertebrae
ribs
sternum
sacrum

The ribs, sternum, and thoracic vertebrae form a structure called

bony thorax

Encloses the brain

cranium

Forms the structure of the face

facial bones

Bones that make up the cranium

frontal
parietal
2 temporal
occipital
sphenoid
ethmoid

Facial bones include

maxillae
palatine
zygomatic
lacrimal
nasal
inferior nasal conchae
mandible
vomer

What facial bones are unpaired

mandible and vomer

The bones of the skull articulate with each other by joints called

sutures

The joint between the frontal bone and the parietal bones

coronal suture

The joint between each parietal bone and the corresponding temporal bone

squamosal suture

The joint between the occipital bone and the mastoid process of each temporal bone

occipitomastoid suture

The joint between the left and right parietal bones

sagittal suture

The joint between the left and right parietal bones and the occipital bone

lambdoid suture

This suture traverses the crown of the skull

coronal suture

This suture follows the sagittal plane of the skull

sagittal suture

This suture is named for its resemblance to the Greek letter lambda

lambdoid suture

The bones of the eye socket

frontal
sphenoid
zygomatic
maxillary
lacrimal
ethmoid
palatine

The cavities in the skull

sinuses

The sinuses communicate with the nasal cavity through

ostia

The largest sinuses

maxillary sinuses

Sinuses function

lighten bones of the face
provide resonance chambers for the voice

Inflammation of the sinuses

sinusitis

This bone is in the throat and superior to the larynx

hyoid bone

Hyoid bone function

attachment for many muscles of the tongue and neck

Types of vertebrae of the vertebral column

cervical
thoracic
lumbar
sacral
coccyx

Number of cervical vertebrae

7

Number of thoracic vertebrae

12

Number of lumbar vertebrae

5

Number of sacral vertebrae

5 fused

Number of coccygeal vertebrae

4 fused

This feature of the vertebra faces the anterior side of the column

centrum

This feature of the vertebra faces the posterior side of the column

vertebral arch

The body and the arch together form the

vertebral foramen

Forms the spinal cavity

vertebral foramina

This projects from the vertebral arch

processes

The primary distinguishing features of the cervical vertebrae

transverse foramina

The transverse foramina function

forms the passages for vertebral arteries

The vertebral foramen is triangular in which part of the vertebral column

C3-C7

The spinous process is bifurcated in which part of the vertebral column

C2-C6

Lightest and smallest vertebrae

cervical vertebrae

The first cervical vertebra name

atlas

The atlas lacks a

body

The structure within the atlas to receive the occipital condyles of the skull

superior articular processes

The second cervical vertebra

axis

The superior portion of the body of the axis is modified into this

odontoid process

The primary distinguishing feature of the thoracic vertebrae

costal demifacets

The thoracic vertebrae connect to the

ribs

T1-T11 have an articular facet on the transverse process for the ________ of a rib

tubercle

Which thoracic vertebrae lacks an articular facet

T12

The thoracic vertebrae forms

the posterior portion of the bony thorax

This kind of vertebrae tend to be larger and heavier

lumbar vertebrae

Spinous processes of the lumbar vertebrae

blunt and square

The primary feature of the lumbar vertebrae

lack features of the other vertebrae (transverse foramina, costal demifacets)

consists of 5 vertebrae that fuse together during development

the sacrum

The sacrum with the innominate bones forms the

bony pelvis

Parts of the bony thorax

ribs
sternum
costal cartilages
thoracic vertebrae

Bony thorax function

encloses and protects the internal organs of the thoracic cavity

The parts of the sternum

manubrium,
body,
xiphoid process

This part of the sternum tends to ossify with age, but in most younger people it is still cartilage

xiphoid process

This articulates with the ribs via the costal cartilages

the sternum

This category of ribs have their own cartilage joining them to the sternum

true ribs

How many true ribs are there

7

These ribs share or lack a cartilage joining them to the sternum

false ribs

False ribs include which ribs

8-12

These ribs lack a connection to the sternum

floating ribs

Floating ribs are number

11-12

The typical rib features

head
neck
tubercle
angle
shaft

The head of a rib articulates with the

costal demifacets of two thoracic vertebrae

The tubercle of a rib articulates with the

transverse facets of a single thoracic vertebra