Axial Skeleton Flashcards
What’s in axial Skeleton
Skull, vertebral column, thorax
Function of axial skeleton
Protects the CNS and vital organs
How many bones are in the skull
29
Skull is divided into…
Cranial and facial bones
Mandible
Lower jaw, holds lower teeth
Posterior part of temporal bone has a bump
Mastoid process
Condyle of mandible joins the temporal bone to form
TMJ
Elevation or bump on occipital bone
External occipital protuberance
Roof of orbit
Frontal bone
Holds the pituitary gland
Sella Turcica
Centrally located, keystone of skull
Sphenoid bone
Located between orbital cavities
Ethmoid bone
Perpendicular plate in the ethmoid bone forms the
Bony part of nasal septum
Projects into floor of cranium anterior lay
Crista Galli
Depressions in floor of cranium on which the brain rests
Cranial fossae
Three types of cranial fossae
Anterior, middle, and posterior
Outgrowths of the nasal cavity into the maxillary, ethmoid, frontal, and Sphenoid bones
Paranasal sinuses
What reduces weight of the face
Paranasal sinuses
Order of paranasal sinuses
Frontal
Ethmoid
Sphenoid
Maxillary
Bones of orbit….
Roof (frontal bone)
Floor (axillary bone)
Medial and lateral wall (ethmoid, zygomatic)
In the fetal skull, cranial bones are…
Joined by CT
Slide over one another in childbirth
Large areas of connective tissue where some bones intersect
Fontanelles
U-shaped bone, in the upper neck
Hyoid bone
Attachment sites for tounge and neck
Cornus/ horns
Functions of the vertebral column
Structural support
Posture
Protects spinal cord
How many individual vertebrae are there
24
How many cervical, thoracic, lumbar, and sacrum bones
Cervical : 7
Thoracic: 12
Lumbar: 5
Sacrum: 5
Exaggerated thoracic curve (old people)
Kyphosis
Exaggerated lumbar curve (pregnant)
Lordosis
Abnormal curve in the coronal plane
Scoliosis
What houses the spinal cord
Vertebral canal
Features of vertebrate
Large disc like body located anteriorly
Between each body is an…
Intervertebral disc
Located between bodies of adjacent vertebrae
Invertebral discs
Flexion
Forward bending, stretches posterior disc
Extension
Backward bending, stretches anterior disc
Features of invertbral discs
Account for 1/4 th of entire vertebral column
Act as shock absorbers and provide flexibility
First cervical vertebrae?
Atlas, ring of bone with no spinous process
Second cervical vertebrae
Axis, has dens
True or false
Significant amount of cervical rotation occurs between atlas and axis
True
C7 name
Vertebra prominens
Allow vertebral arteries to ascend from the lower neck upward to cranium to supply blood to brain
Transverse foramina
Breast bone
Sternum
How many ribs
12 pairs
What is the sternum made up of
Xiphoid process, body, and manubrium
What ribs are true, false, and floating
True: 1-7
False: 8-12
11 and 12 are floating
Each rib has a
Head, neck, and tubercle
Movement of ribs
Elevation and depression
Have long spinous processes that are angled inferiority
Thoracic vertebrae
What articulates with the ribs
Thoracic vertebrae
Largest vertebrae
Lumbar
What bears most of the body weight
Lumbar
Triangular bone composed of 5 fused vertebrae
Sacrum
4 small fused vertebrae, tail bone
Coccyx
5 movements of the spine
Flexion, extension, abduction, addiction, rotation
