The skull Flashcards
How many bones does the skull contain?
The skull has 22 bones, excluding the ossicles of ear , except for th
How is the mandible joined to the skull?
The mandible is joined to the skull by a moveable joint
Describe most of the skull bones and what are the skull bones joined by?
Most skull
bones are flat bones joined by
interlocking joints called sutures
What is the skull divided into?
The skull is divided into the braincase (neurocranium) and the facial skeleton (viscerocranium).
What is the main task of the skull?
The main task of the skull is the protection of the most important organ in the human body: the brain.
Name the 8 cranial bones of the skull.
- Occipital
- 2 Temporal bones
- 2 Parietal bones
- Sphenoid
- Ethmoid
- Frontal
Name the 14 facial bones.
- 2 Nasal
- 2 Maxillae
- 2 Zygomatic
- Mandible
- 2 Lacrimal
- 2 Palatine
- 2 Inferior nasal conchae
- Vomer
List the functions of the skull.
The skull : • Forms the framework of the face • Contains cavities for special sense organs • Provides openings for air & food passage • Secures the teeth • Anchors muscles eg. muscles of facial expression & mastication
What is the cranium divided into?
The cranium is divided into :
An upper domed part (calvaria) that covers the cranial cavity containing the brain
• A Base that consists of floor of cranial cavity
• The Lower anterior part- facial skeleton (viscerocranium)
Name the bones that make up the calvaria.
CALVARIA
Temporal & parietal bones
Frontal, sphenoid, & occipital bones
Name the bones that make up the cranium.
CRANIUM
Sphenoid, temporal, & occipital bones
Name the bones that make up the facial skeleton.
FACIAL SKELETON Nasal bones Palatine bones Lacrimal bones Zygomatic bones Maxillae Inferior nasal conchae Vomer
Describe the roof of the calvaria.
The calvaria roof is a dome-shaped roof
What is the function of the roof of the calvaria?
The calvaria roof protects the superior aspect of brain
What does the roof of the calvaria consist of?
The calvaria roof Consists mainly of the frontal, paired parietal, & occipital bones
Calvaria - What is the frontal crest?
The frontal crest is the point of attachment for the falx cerebri
What is the purpose of the depressions and pits(granular foveolae)?
The depressions and pits mark the location of the arachnoid granulations
What creates the smaller grooves?
The smaller grooves are created by various meningeal vessels
Where are the 4 largest sutures of skull located?
The four largest sutures of the skull are located where the parietal bones articulate with other bones:
coronal, sagittal, lambdoid sutures
Which bones make up the calvaria/skull cap?
Frontal bone, parietal bones, & occipital bone
What does the unpaired frontal articulate with?
The unpaired frontal bone
articulates with paired parietal bones at coronal
suture
What do the 2 parietal bones articulate with?
The two parietal bones
articulate with each other
in midline at sagittal suture
Which unpaired bone do parietal bones articulate with?
The Parietal bones articulate
with the unpaired occipital
bone at the lambdoid suture
What is the junction of the sagittal and coronal sutures called?
Junction of sagittal & coronal sutures is bregma
What is the junction of the sagittal and lambdoid sutures called?
Junction of sagittal & lambdoid sutures is lambda
What does the frontal bone form?
The frontal bone forms the forehead, roof of
orbit, most of anterior
part of cranial floor
What happens to the right and left frontal bones after birth?
After birth the right & left frontal bones unite at the
metopic suture
What takes place superior to the orbit?
Superior to orbit, bone
thickens – forms supra-orbital margin- contains
foramen
Incomplete foramen =
supraorbital notch
Where do the frontal sinuses lie?
Frontal sinuses lie deep
to frontal squama
Which bones form the sides and the roof of the cranial cavity?
Two parietal bones form sides & roof of cranial cavity
CRANIAL BONES … PARIETAL BONE. What does the internal surface contain?
The internal surface contains many protrusions & depressions that accommodate blood
vessels supplying dura mater
What do the temporal bones form?
The temporal bones form the inferior lateral aspect of cranium + part of cranial floor
What forms the zygomatic arch?
The zygomatic process of temporal and the temporal process of zygomatic bone
