Axial Skeloton Flashcards
Understand Skeleton Axial
skeleton
dried up body, composed of bones, cartilages, joints and ligaments
Skeleton accounts for what percentage of body mass?
20%
What is the skeleton’s main component?
bones
Function of ligaments
connects bones and reinforce joints
Joints
the junction between bones
Two parts of skeleton
Axial and appendicular
Axial
80 bones
skull
vertebral column
thoracic cage
Appendicular
bones of the limbs and their girdles
Three regions of the axial skeleton?
skull
vertebral column
thoracic cage
bony thorax
How many bones in axial ?
80 bones are in the axial skeleton
Skull
the body’s most complex bony structure
What is the skull formed by?
the cranium and facial bones
How many bones are in the cranium?
8
how many bones are in the facial bones?
14
Cranium
protects brain and is the site of attachment for head and neck muscles
Facial bones supply the frame work of what?
face, sense organs, and the teeth
Facial bones provide what?
openings for the passage of air and food
Facial bones anchor?
the facial muscles of expression (smiling)
What are the eight cranial bones comprised of?
2 parietal Ethmoid 2 temporal Sphenoid frontal occipital
Cranial Bones are desrcibed as what?
thin and strong for their weight
foramen
opening in bones for nerves and blood vessels to pass through
frontal bone forms what?
the anterior portion of the cranium
frontal bone articulates ?
posteriorly with the parietal bones via the coronal suture
processes mean?
point of muscle attachment
suture
an immobile joint
How many sutures that mark the articulations of the parietal bones?
4
What are the four sutures for parietal bones?
Coronal, Sagittal, Lamboid, and squamosal sutures
coronal suture
articulation between parietal bones and frontal bone anteriorly
sagittal suture
where right and left parietal bones meet superiorly
lambdoid suture
where parietal bones meet the occipital bone posteriorly
squamosal suture
where parietal and temporal bones meet
How many parietal bones in skull?
2
How many occipital bones?
1
occipital bones forms?
most of skulls posterior wall and base
Occipital bones major markings?
posterior cranial fossa, foramen magnum, and occipital condyles
condyles
round smooth surface
Temporal Bones form
the inferolateral aspects of the skull and parts of the cranial floor
temporal floor is divided into four regions:
squamous, tympanic, mastoid, and petrous
Major markings of temporal bones
zygomatic, styloid, and mastoid processes, and the mandibular and middle cranial fossae
temporal bones major openings
stylomastoid and jugular foramina, the external and internal auditory meatuses, and the carotid canal
sphenoid bone
butterfly-shaped bone that spans the width of the middle cranial fossa
sphenoid bone forms?
the central wedge that articulates with all other cranial bones
sphenoid bones has?
central body
greater wings
lesser wings
Ethmoid Bone
Most deep of the skull bones; lies between the sphenoid and nasal bones
Ethmoid bone forms
most of the bony area between the nasal cavity and the orbits
Facial Bones
14 bones of which only the mandible and vomer are unpaired
Facial bones paired bones are?
maxillae, zygomatics, nasals, lacrimals, palatines, and inferior conchae
Mandible
Lower jawbone
largest, strongest bone on the face
Mandible major markings
coronoid process
mandibular condyle
alveolar margin
mandibular and mental foramina
Maxillary bones
medially fused bones that make up the upper jaw and the central portion of the facial skeleton
Maxillary bones facial keystone bones that articulate with?
all other facial bones except the mandible
Zygomatic Bones
irregularly shaped bones (cheekbones) that form the prominences of the cheeks and the inferolateral margins of the orbits
Nasal Bones (facial)
thin medially fused bones that form the bridge of the nose
(facial)lacrimal bones
contribute to the medial walls of the orbit and contain a deep groove called the lacrimal fossa
(facial)Palatine bones
two bone plates that form portions of the hard plate, the posterolateral walls of the nasal cavity, and a small part of the oribits
Vomer (facial)
plow-shaped bone that forms part of the nasal spetum
Inferior Nasal Conchae
facial
paired
curved bones in the nasal cavity that form part of the lateral walls of the nasal cavity