Axial skeleton Flashcards
(44 cards)
How many bones are in the axial skeleton and what are the main groupings?
80 bones. Skull, Spine, chest, and hyoid
How many bones are in the skull?
22 + 6 ear ossicles.
How many bones are there in each region of the skull
-8 cranial bones
-14 facial bones
-Top part of the skull
-Cavity that holds the eyes and their appendages
-Calvaria
-Orbit
What are the cranial bones and how many are there of each?
-Frontal bone (1)
-Parietal bones (2)
-Occipital bone (1)
-Temporal bones (2)
-Sphenoid bone (1)
-Ethmoid bone (1)
Forehead bone, forms the upper part of the eye socket
Frontal bone
What are these and where are they found?
1. Superior boundary of the orbit
2. ridge superior to the eye socket
3. slight depression the joins the brow ridge
4. rounded elevation on the frontal bone
5. sinus within the frontal bone
Features of the frontal bone.
1. Supraorbital margin
2. Superciliary arch
3. Glabella
4. Frontal eminence
5. Frontal sinus
Form the top sides of the cranium
Parietal bones
- Slight eminence in the center of each parietal bone
Feature of the parietal bone.
1. Parietal eminence
Forms the back of the skull
Occipital bone
What are these and where are they found?
1. Rounded knobs that form a joint with the first cervical vertebrae
2. Opening where the spinal chord enters the cranium
3. Bony prominence in the middle of the occipital bone where the posterior wall meets the base of the skull
Features of the occipital bone.
1. Occipital condyles
2. Foramen magnum
3. External occipital protuberance
Inferior and lateral portion of the cranium
Temporal bones
What are these the divisions of and where?
1. Squamous portion
2. Petrous portion (what does this house?)
Temporal divisions.
1. Anterior/ superior
2. Posterior/ inferior. Houses the inner eat components and the Carotid canal
The passageway in the temporal bone which the inner carotid artery passes
Carotid canal
What are these and how many?
1. Hammer shaped bones
2. Anvil shaped bones
3. Stirrup shaped bones
Inner ear ossicles
1. Malleus (2)
2. Incus (2)
3. Stapes (2)
What are these and where are they found?
1. Projection at the base of the temporal bone
2. The depression in the temporal bone into which the condyle of the mandible fits
3. the lateral, outer opening of the ear or auditory canal
4. process projecting from the lower squamous portion articulating with the temporal process on the zygomatic bone forming the zygomatic arch
Features of the temporal bones.
1. Mastoid process
2. Mandibular fossa
3. External auditory meatus
4. Zygomatic process
Forms the central part of the cranial floor
Sphenoid bone
What are these and where are they found?
1. Depression in the floor of the sphenoid bone (contains the pituitary gland)
2. Sinuses within the sphenoid bone
Features of the sphenoid bone
1. Sella turcica
2. Sphenoidal sinuses
Anterior skull bone that forms parts of the cranial floor, nasal septum, and parts of the nasal cavity
Ethmoid bone
What are these and where are they found?
1. Forms the roof of the nasal cavity
2. Anterior triangular wedge projecting superiorly into the cranial cavity
3. Flat plate extending from under the cribriform plate
4. Sinuses within the ethmoid bone
Features of the ethmoid bone.
1. Cribriform plate
2. Crista galli
3. Perpendicular plate
4. Ethmoid sinuses
What are the facial bones and how many are there of each?
-Nasal bones (2)
-Lacrimal bones (2)
-Zygomatic bones (2)
-Palatine bones (2)
-Maxillary bones (2)
-Vomer (1)
-Inferior nasal conchae (2)
-Mandible (1)
Form the upper part of the bridge of the nose
Nasal bone
Inner-cranial bone that forms the medial wall of the eye socket
Lacrimal bones
Cheek bones
Zygomatic bones
