Axial Skeleton Flashcards
The axial skeleton is composed of 2 regions. What are they?
The skull and the trunk (the neck to coccyx)
What does the axial skeleton serve as?
It protects the central nervous system within the cranial and vertebral cavities, protects the heart and lungs, facilitates ventilation of the lungs and attaches to the limbs
What are the 4 main bold faced functions of the skeleton?
- Support
- Protection
- Movement
- Blood formation
Explain the function of support
the weight of the body is supported by the skeletal system
Explain the function of protection
Bones protect the structures within: bone marrow, brain, spinal cord and visceral organs
Explain the function of movement
Muscles act on bones to bring about movements; electrolyte balance: bone tissue stores calcium and phosphate ions that can be released as needed to maintain ionic homeostasis
Explain the function of blood formation
Red bone marrow is found within many bones; it produces red blood cells, white blood cells and platelets
Define a head (bone terminology)
a rounded enlargement at the end of a bone
Define a neck (bone terminology)
the narrow region immediately adjacent to the head
Define a body
the main part apart from other named parts
Define a tubercule
a bump or elevation
Define a process
a bony projection from the surface
Define a fissure
an elongated hole or irregular opening
Define a meatus
an opening or canal
Define a foramen
a hole or opening
Define a sinus
an air filled cavity within a bone
The axial skeleton includes:
the skull, vertebral column, ribs and the sternum
Why is the vertebral column important
for locomotion and posture
The vertebral column has many attachments to ___
muscles
The ribs and sternum are protective to organs of the ?
thoracic cavity
what are the 5 regions that consist of anatomically distinct vertebrae
cervical, thoracic, lumbar, sacral and coccygeal
The vertebral column has several what
curve
what kind of curves are the cervical and lumbar regions
concave from a posterior perspective
what kind of curves are the thoracic and sacral regions
convex
how many vertebrae is the vertebral column composed of
33 vertebrae
what is found in between the 33 vertebrae
intervertebral discs
define “body” in relation to the vertebrae
the weight bearing region of the vertebra - vertebral bodies become larger in the lower regions of the vertebral column and bear more of the body’s weight
define “vertebral foramen” in relation to the vertebrae
location of the spinal cord
define “spinous” and “transverse processes” in relation to the vertebrae
sites of muscle attachments
Define superior articular processes and inferior articular processes
forms joints with those of adjacent vertebrae ; they are responsible for restricting movements of vertebral column
define the intervertebral foramina
above and below the pedicles of each vertebra a notch is carved out that allows for the passage of a spinal nerve
define pedicle in relation to the vertebra
connects body to rest of vertebra
define lamina in relation to the vertebra
connects spinous process to rest of vertebra
how many cervical vertebrae allow great flexibility in the neck
7
what does a transverse foramen do
it easily identifies the 7 vertebrae that allow flexibility in the neck and allows passage of the vertebral artery, a significant blood supply to the brain
what is the first cervical vertebrae
C1 - the atlas - it has no vertebral body and serves to articulate with the skull
Movement between the skull and C1 is in what plane?
the sagittal plane
What is the C2 vertebrae?
the axis; below C1; is unique among cervical vertebrae
what does the C2 axis have that makes it unique
it has a projection called the dens (or odontoid process) that fits into the large vertebral foramen of C1
what does the dens do?
it prevents C1 from slipping posteriorly and it allows rotation between C1 and C2
C3 - C7 cervical vertebrae are pretty __ to one another
similar
which vertebrae is called vertebra prominens and why
C7 - because of its long spinous process that can be easily palpated in most people
