Axial Skeleton - Chapter 7 Flashcards
The axial skeleton consists of?
skull, skull and associated bones, vertebral column, and thoracic cage
Parietal bones are an attachment site for?
temporalis muscle
The parietal eminence is
rounded prominence on each side of skull
3 parts of temporal bone
petrous, squamous, and tympanic
Temporal bones make up
inferior lateral wall and part of cranium floor
mastoid process is attachment site for
some neck muscles
styloid process is attachment site for
typhoid and tongue muscles
What is the job of the temporomandibular joint
attach the lower jaw to the rest of skull
The occipital bone is located
posterior region and portion of base of the cranium
The sphenoid bone is also known as?
The bridging bone
The sphenoid bone’s (bridging bone) job is to
unite facial and cranial bones, articulations with most bones of skull bone
The Ethmoid bone is located
at the roof of the nasal cavity, part of the nasal septum
Crista Galli is the attachment for
falx cerebri (covering of brain)
Cribriform plate is the
passageway for olfactory nerves
The Ethmoidal labyrinths contain
the ethmoid sinuses
The coronal suture is located where?
between front and parietal skull bones
The lambdoidal suture is located where?
between the occipital and parietal bones
The sagittal suture is located where?
between the parietals
The squamous suture is located where?
between the temporal and parietal
What is a fossa?
depression in a bone(s)
How many facial bones are there?
14 ( pairs of each except the maxillae, vomer, and mandible)
The Zygomatic Bone is also known as the?
cheek bone
the zygomatic bone is located where?
the lateral wall of orbit and cheek
The lacrimal bone is located where?
the medial wall of the orbit
What is the function of the lacrimal groove?
it is a passageway for the nasolacrimal duct
The inferior nasal cavity serves what function?
act to create turbulence in inhaled air
The Palatine Bone is
the L shaped bone
The horizontal plate articulates with
the palatine process of the maxilla
the orbital process of perpendicular plate forms part of what?
medial floor of orbit
The Maxilla forms what?
the upper jaw
The Vomer forms what?
lower half of nasal septum; is a triangular shape
the mandible involves the
body and ramus
The mental protuberance forms the
chin
The Nasal Complex is comprised of the…
bones and cartilage forming the nasal cavities and sinuses around them
How many bones are part of the Nasal Complex?
7 bones
What are the paranasal sinuses?
air-filled spaces in skull bones around nasal cavity
The function of mucus in paranasal sinuses
humidifies and warms inhaled air
4 major types of paranasal sinuses
Frontal, Ethmoid, Sphenoid, and maxillary
The orbits are
bone cavities in skull that hold and protect eye
Auditory ossicles function?
the 3 tiny bones in each temporal for hearing
What are the Auditory Ossicles
Malleus, incus, stapes
Fontanelles are?
flexible areas of dense regular connective tissue that connect infant cranial bones together
2 major fontanelles
Anterior fontanelle and posterior fontanelle
Anterior fontanelle ossifies at how many months?
ossifies at ~15 months
Posterior fontanelle ossifies at how many months?
ossifies at ~9 months
The spinal cord consist of what?
all vertebral foramen together
The intervertebral foramen consist of
2 vertebral notches together
Vertebral bodies are interconnected by what?
ligaments
Annulus fibrosis is the
outer fibrocartilaginous ring
Nucleus pulposus is the
inner circular region of intervertebral disc
Function of Nucleus pulposus?
absorbs vertical shock and permits various movements of the vertebral column
cervical vertebrae are
smaller bodies with larger spinal canal
thoracic vertebrae are
larger and stronger bodies
lumbar vertebrae are
shortest and largest bodies
Atlas (C1)
lacks body
The Atlas makes what type of movement?
nodding movement
How is nodding movement at atlanto-occipital joint signifies…
“yes” - head nod (up and down)
Axis (C2)
has dens attached
The Axis makes what type of movement?
pivotal movement
How is the pivotal movement at atlanto-occipital joint signifies…
“no” - head shake (side to side)
The Axis acts as
axis of rotation between the atlas and the skull
When does the sacrum fuse?
the third decade of life
What does the sacrum serve as?
foundation for pelvic girdle
Where does the spinal canal end?
sacral hiatus
The Sacrum was originally how many vertebrae?
5
When does the Coccyx fuse?
the third decade of life
The Coccyx was originally how many vertebrae?
4
The sternum is also known as
the “breastbone”
The sternum is originally comprised of how many vertebrae?
3
At what age does the sternum fuse?
approximately 40 years of age
That Xiphoid process ossifies by what age?
40 years old
How many pairs of ribs are there?
12 pairs
True ribs are which rib pair numbers
1 - 7
Where do true ribs anchor to
directly to sternum
False ribs are which rib pair numbers
8 - 12
False ribs
do not articulate directly with sternum via their coastal cartilages
Floating ribs are which rib pair numbers
11 and 12
