ANATOMY PART 1- Bones of the Skull

Question 1

of bones in the cranium?
divided into what 2 sections?
cranial cavity divided into?

Answer 1

22 bones
neurocranium and viscerocranium
upper domed part and the base of the skull

Question 2

Cranial Sutures (synarthrosis)

Answer 2

coronal, sagittal, lambdoid, squarrious

Question 3

Synarthrosis/Suture

Answer 3

A suture is a type of synarthrosis- a joint that allows little to NO movement

• developed after birth over course of 2 YEARS
• flexible in INFANCY/early childhood
  (fibrous strong immobile bands between immovable bones)

Question 4

Fontanels

Answer 4

soft membrane gaps between cranial bones of calvaria
- allow rapid growth of brain
- close after birth, this is what allows them to move through birth canal since its flexible

Question 5

6 Fontanels

Answer 5

posterior, anterior, (left and right) posterolateral (mastoid), anterolateral (sphenoid)

Question 6

Craniosynostosis

Answer 6

pathological process leading to complete ossification PREMATURELY (of the fontanels)

Question 7

Neurocranium

Answer 7

composed of calvaria, skull roof formed by flat bones and cranial base, cartilaginous part, delimitates the cranial cavity, communicates below the vertebral canal through foramen magnum

calvaria=top part of skull
this is split up into the frontal, occipital

Question 8

Calvaria

Answer 8

upper part of neurocranium
- composed of FLAT bones
- smooth outer convex surface, inner concave surface

Question 9

Diploe

Answer 9

cancellous (spongy) bone tissue containing bone marrow and diploic veins

diploic veins are va

inner layer of skull bone that looks like a sponge

Question 10

Frontal bone

Answer 10

forehead and superior rim of the orbit
- pneumatized bone (hollow) is superiro to each orbital rim
- glabella (area of skin between eyebrows above the nose) forms MEDIAL rim of orbit
- laterally the frontal bone extends with the frontal

Question 11

Frontal Bone Articulations

Answer 11

joins parital bones through coronal suture
- greater wing of sphenoid
- frontal process of zygomatic bone
- through zygomatic process
- nasal and lacrimal bones

Question 12

Parietal Bone

Answer 12

forms room and sides of the cranium
- composed of 2 SURFACES, 4 ANGLES, and 4 MARGINS
- angles: frontal, occipital, sagittal, squamous
- margins: frontal, sphenoid, mastoid, occipital

Question 13

Occipital Bone

Answer 13

trapezoidal curved bone which overlies the occipital lobes
- 4 parts: squamous, basilar, 2 lateral parts than contain a large opening where the spinal cord passes (foramen magnum)
-

Question 14

Inner Occipital Surface

Answer 14

base of posterior cranial fossa, where the foramen magnum is bound

Question 15

Exterior Occipital View

Answer 15

internal elements correspond to the outer surface
- 3 transversal nuchal lines
- 2 occipital condyles on each side of foramen magnum (articulate with the atlas)

Question 16

Temporal Bone

Answer 16

paired flat bone on sides of cranium
- houses structures of ears
- 4 parts: squamous, zygomatic process, tympanic and styloid, petromastoid

Question 17

Cranial Base

Answer 17

floor of cranial cavity
- 2 surfaces: endocranium and external cranial base
- sphenoid, ethmoid, occipital, frontal, temporal bone

Question 18

Ethmoid Bone

Answer 18

small unpaired bone
- separates nasal from cranial cavity
- superior projection
- small portion of orbit

Question 19

Sphenoid Bone

Answer 19

butterfly shaped unpaired bone
- anterior to basilar of occipital
- sphenoidal sinuses
- body, greater wings, lesser wings, ptygeroid

Question 20

Viscerocranium

Answer 20

facial skeleton located ANTERIOR to neurocranium
- supports facial features
- 14 BONES
- joined through synarthroses except mandible (jaw moves)

Question 21

Zygomatic Bone

Answer 21

irregular paired bone, form face lateral prominences (cheekbones)
- parts of orbit inferior and lateral rims
- 4 processes, 3 surfaces, 4 borders

Question 22

Nasal Bone

Answer 22

small oblong paired bones
- forms nose bridge
- articulates medially through internasal suture
- each side has 2 surfaces, articulate frontal bone, inferiorly with maxillae

Question 23

Maxillae

Answer 23

large paired bones, hold upper teeth
- formation or orbit, nasal cavity, and palate
- 4 processes: zygomatic, frontal, alveolar, palatine

Question 24

Palatine Bone

Answer 24

irregular paired bones, alongside maxillae
- forms hard palate, between maxilla and pterygoid process
- fuse on midline, 2 perpendicular plates