The Skull

Question 1

Functions of the skull?

Answer 1

Enclose and protect brain and special sense organs Create a specialised environment in which the brain can thrive (cranial cavity) Attachment of muscle and meninges

Question 2

What are the three layers of the bones in the cranium?

Answer 2

Outer plate -compact bone

Diploe-Spongy bone (reduces the weight)

Inner plate - compact bone

Question 3

Which bones form the cap of the cranium?

Answer 3

Frontal Parietal Occipital Temporal

Question 4

What grooves does the parietal bone have?

Answer 4

Grooves of: -middle meaningeal artery -sagittal sulcus -granular pits -sigmoid sulcus

Question 5

What are the four parts of the occipital bone arranged around?

Answer 5

Foramen magnum

Question 6

Which bones form the floor of the calvaria? (Aka cranial fossa, cranial base)

Answer 6

Sphenoidal Ethmoid Temporal

Question 7

Features of the sphenoid bone?

Answer 7

Has the sphenoid sinus Greater and lesser wings Pterygoid process Optic groove

Question 8

What can fracture of the ethmoid bone lead to?

Answer 8

Anosmia (loss of sense of smell)

Question 9

Features of the temporal bone?

Answer 9

Zygomatic process, squamous, External auditory meatus(tympanic) , mastiod process, Madibular fossa (articulate with TMJ), articular tubular, Styloid process, styliod mastoid foramen,

Question 10

What do the bones of the cranial base provide articulation for?

Answer 10

C1 (atlas) Facial bones Mandible

Question 11

Name the bones of the facial skeleton

Answer 11

Zygomatic Lacrimal Nasal Inferior nasal conchae Palatine Vomer Maxillae Mandible Frontal

Question 12

What are the main sutures in adulthood?

Answer 12

Coronal suture - between frontal and parietals Saggital - between both parietals Lambdoid - occipital with parietals Visualise it!

Question 13

What are fontanelles?

Answer 13

Incompletely fused suture joints in neonates

Question 14

Which bones form each of the cranial fossas?

Answer 14

Anterior - depression formed by frontal, ethmoidal and parietal Middle - depression formed by sphenoid, temporal, parietal Posterior - squamous, mastoid temporal bone, occipital bone

Question 15

What makes the bones of the skull less easily unlocked?

Answer 15

The edges are serrated

Question 16

Which bones are most frequently broken in a facial fracture?

Answer 16

Nasal

Question 17

Frontal Bone

Answer 17

the large cranial bone forming the front part of the cranium: the forehead and the upper part of the orbits

Question 18

Frontal sinus

Answer 18

one of a pair of cavities in the frontal bone

Question 19

Glabella

Answer 19

The smooth area between the eyebrows just above the nose

Question 20

Supraorbital Foramen

Answer 20

small opening superior to each eye socket

Question 21

Parietal Bone

Answer 21

either of two skull bones between the frontal and occipital bones and forming the top and sides of the cranium

Question 22

Temporal Bone

Answer 22

a thick bone forming the side of the human cranium and encasing the inner ear

Question 23

Mastoid Process

Answer 23

process of the temporal bone behind the ear at the base of the skull

Question 24

Mandibular Fossa

Answer 24

the depression in the temporal bone into which the condyle of the mandible fits.

Question 25

Zygomatic Process

Answer 25

part of the temporal bone that forms part of the cheekbone

Question 26

Styloid Process

Answer 26

pole like process extending downward from the temporal bone on each side of the skull

Question 27

Internal Acoustic Meatus

Answer 27

a canal in the petrous part of the temporal bone of the skull

Question 28

Foramen Magnum

Answer 28

the large opening at the base of the cranium through which the spinal cord passes

Question 29

Occipital Bone

Answer 29

the bone found at the back and base of the skull

Question 30

Occipital Condyles

Answer 30

rounded projections lateral to the foramen magnum that articulate with the first cervical vertebra (atlas)

Question 31

midline prominences posterior to the foramen magnum

Answer 31

External Occipital Protuberance

Question 32

Ethmoid Bone

Answer 32

irregularly shaped bone anterior to the sphenoid. Forms the roof and upper septum of the nasal cavity and part of the medial orbit walls.

Question 33

Crista Galli

Answer 33

superior projection in the middle of the cribriform plate of the ethmoid bone

Question 34

Cribriform Plate

Answer 34

porous bone surrounding the crista galli in the floor of the cranium through which olfactory nerves transverse

Question 35

Sagittal Suture

Answer 35

midline articulation point of the two parietal bones

Question 36

Coronal Suture

Answer 36

the suture between the parietal and frontal bones of the skull

Question 37

Squamousal Suture

Answer 37

the suture found between the parietal & temporal bone

Question 38

suture that separates parietal bones from occipital bone

Answer 38

Lambdoidal Suture

Question 39

the suture between the two ossification centers of the frontal bone, it usually disappears during development but is occasionally present in adults

Answer 39

Metopic Suture