The Skull

Question 1

Axial Skeleton vs. Appendicular

Answer 1

Axial:
-Bones of skull*
-Accessory bones*
-Vertebral column
-Thoracic cage

Appendicular:
-Upper limbs and pectoral girdle
-Lower limbs and pelvic girdle

Question 2

The Skull 2 Components

Answer 2

1. Neurocranium- braincase
2. Viscerocranium- facial skeleton

Question 3

Bones in the skull #

Answer 3

Total= 22

Neurocranium= 8 (2 pairs)
Viscerocranium= 14 (6 pairs)
Accessory= 7

Question 4

Bones of the Neurocranium

Answer 4

Parietal (2)
Temporal (2)
Frontal (1)
Occipital (1)
Ethmoid (1)
Sphenoid (1)

Question 5

Bones of the Viscerocranium

Answer 5

Maxillae (2)
Palatine bones (2)
Nasal bones (2)
Inferior nasal conchae (2)
Zygomatic bones (2)
Lacrimal bones (2)
Vomer (1)
Mandible (1)

Question 6

Functions of the Skull

Answer 6

Neurocranium:
-surrounds and protects brain
-articulates with vertebral column

Viscerocranium:
-supports and protects entrances to digestive and respiratory tracts

Accessory bones:
-7 bones for hearing and muscle attachment

Question 7

4 External Features of the Temporal Bone

Answer 7

1. External acoustic meatus
2. Mastoid process
3. Styloid process
4. Zygomatic process

Question 8

2 Features of the Occipital Bone

Answer 8

1. Foramen magnum- passage of spinal cord
2. Occipital condyle- articulation with C1 (atlas)

Question 9

2 Features of the Ethmoid

Answer 9

-Crista Galli
-Cribriform Plate

Question 10

Crista Galli

Answer 10

-Perpendicular projection of ethmoid bone
-Acts as an anchoring point for membranes surrounding the brain (meninges)

Question 11

Cribriform Plate

Answer 11

Branches of CN I (olfactory nerve) passes through plate of ethmoid bone

Question 12

Features of the Sphenoid

Answer 12

Greater and lesser wings, pterygoid processes, sella turcica

Question 13

Sella Turcica

Answer 13

Feature of the sphenoid, holds the pituitary gland

sella turcica= turkish saddle

Question 14

Skull Foramina of Sphenoid Bone

Answer 14

Optic canal, superior orbital fissure, inferior orbital fissure

Foramen rotundum, foramen ovale, foramen spinosum, foramen lacerum

Question 15

Sutures of the Skull (4)

Answer 15

Fibrous, immovable joints (boundaries b/t skull bones)

Coronal
Sagittal
Lambdoid
Squamous

Question 16

Cranial Fossae (3)

Answer 16

Anterior cranial fossa:
-Frontal lobe of brain
-Frontal, ethmoid, sphenoid bones

Middle cranial fossa:
-Temporal lobes of brain
-Sphenoid, temporal bones

Posterior cranial fossa:
-Cerebellum
-Occipital, temporal bones

Question 17

Temporomandibular Joint (TMJ)

Answer 17

-Only moveable joint of the skull
-Articulation b/t condylar process of mandible, and mandibular fossa of temporal bone

Question 18

Hard palate (2 components)

Answer 18

-Palantine process (of maxilla)
-Palantine bones

Question 19

Accessory Bones of Skull

Answer 19

1. Ossicles- 3 small bones (in middle ear) involved in hearing, housed in temporal bone

1) Malleus
2) Incus
3) Stapes

2. Hyoid Bone- “floating bone” located in neck, important attachment site for tongue and muscles involved in swallowing

Question 20

7 Bones of the Orbit

Answer 20

1. Ethmoid
2. Sphenoid
3. Zygomatic
4. Maxilla
5. Frontal
6. Lacrimal
7. Palatine