Skull

Question 1

diploë

Answer 1

The skull bones are made up of external and internal tables of compact bone separated by a layer of spongy bone called the diploë

Question 2

cranial bones

Answer 2

Frontal bone: 1
■■ Parietal bones: 2
■■ Occipital bone: 1
■■ Temporal bones: 2
■■ Sphenoid bone: 1
■■ Ethmoid bone: 1

Question 3

facial bones

Answer 3

Zygomatic bones: 2
■■ Maxillae: 2
■■ Nasal bones: 2
■■ Lacrimal bones: 2
■■ Vomer:1
■■ Palatine bones: 2
■■ Inferior conchae: 2
■■ Mandible: 1

Question 4

orbital margins

Answer 4

bounded by the frontal bone superiorly
the zygomatic bone laterally
the maxilla inferiorly
processes of the maxilla and frontal bone medially.

Question 5

nasal septum is formed by

Answer 5

vomer & ethmoid

Question 6

parts of the temporal bone

Answer 6

squamous, tympanic, mastoid process, styloid pro- cess, and zygomatic process

Question 7

pterion

Answer 7

the thinnest part of the lateral wall of the skull where the anteroinferior corner of the parietal bone articulates with the greater wing of the sphenoid

it overlies the anterior division of the middle meningeal artery and vein.

Question 8

pterygopalatine fossa

Answer 8

is a small space behind and below the orbital cavity. It communicates laterally with the infratemporal fossa through the pterygomaxillary fissure, medially with the nasal cavity through the sphenopalatine foramen, superiorly with the skull through the foramen rotundum, and anteriorly with the orbit through the inferior orbital fissure

Question 9

ligamentum nuchae attaches to?

Answer 9

external occipital protuberance

Question 10

pterygoid hamulus

Answer 10

The inferior end of the medial pterygoid plate is prolonged as a curved spike of bone

Question 11

anterior clinoid process

Answer 11

the lesser wing of the sphenoid forms the anterior clinoid process on each side, which gives attachment to the tentorium cerebelli.

Question 12

crista galli

Answer 12

is a sharp upward projection of the ethmoid bone in the midline for the attachment of the falx cerebri

Question 13

posterior boundary of anterior cranial fossa

Answer 13

lesser wing of sphenoid

Question 14

floor of anterior cranial fossa

Answer 14

laterally orbital plates of frontal bome

medially by cribriform plate of ethmoid

Question 15

nerve of the pterygoid canal

Answer 15

The greater petrosal nerve enters the foramen lacerum deep to the trigeminal ganglion and joins the deep petrosal nerve to form the nerve of the pterygoid canal

Question 16

arcuate eminence

Answer 16

The arcuate eminence is a rounded eminence found on the anterior surface of the petrous bone and is caused by the underlying superior semicircular canal

Question 17

tegmen tympani

Answer 17

a thin plate of bone, is a forward extension of the petrous part of the temporal bone and adjoins the squamous part of the bone From behind forward, it forms the roof of the mastoid antrum, the tympanic cavity, and the auditory tube. This thin plate of bone is the only major barrier that separates infection in the tympanic cavity from the temporal lobe of the cerebral hemisphere

Question 18

parts of sella turcica

Answer 18

dorsum sellae
tuberculum sellae
hypophysial fossa

Question 19

parts of occipital bone

Answer 19

lateral parts
squamous part
basillar part

Question 20

Perforations in cribriform plate of

Ethmoid bone transmits

Answer 20

Olfactory nerves

Question 21

Optic canal (Lesser wing of sphenoid) transmits?

Answer 21

Optic nerve, ophthalmic artery

Question 22

Superior orbital fissure (Between lesser and greater wings of sphenoid) transmits

Answer 22

Lacrimal, frontal, trochlear, oculomotor, nasociliary, and abducent nerves; superior ophthalmic vein

Question 23

foramen rotundum (gw) transmits

Answer 23

Maxillary division of the trigeminal nerve

Question 24

foramen ovale (gw) transmits

Answer 24

Mandibular division of the trigeminal nerve, lesser petrosal nerve

Question 25

foramen spinosum (gw) transmits

Answer 25

middle meningeal artery

Question 26

foramen lacerum (Between petrous part of temporal and sphenoid) transmits:

Answer 26

internal carotid artery

Question 27

foramen magnum transmits:

Answer 27

Medulla oblongata, spinal part of accessory nerve, and right and left vertebral arteries

Question 28

Hypoglossal canal transmits:

Answer 28

hypoglossal nerve

Question 29

jugular foramen (Between petrous part of temporal and condylar part of occipital) transmits:

Answer 29

Glossopharyngeal, vagus, and accessory nerves; sigmoid sinus becomes internal jugular vein

Question 30

internal acoustic meatus (petrous part of temporal bone)

Answer 30

Vestibulocochlear and facial nerves

Question 31

which structures reinforce the base of the skull?

Answer 31

The petrous parts of the temporal bones and the occipital crests strongly reinforce the base of the skull and tend to deflect linear fractures.

Question 32

In fractures of the anterior cranial fossa, which structure is most likely damaged?

Answer 32

cribriform plate of ethmoid bone
which leads to bleeding from the nose (epistaxis), leakage of cerebrospinal fluid into the nose (cerebrospinal rhinorrhea).

Question 33

In fractures of the posterior cranial fossa

Answer 33

blood may escape into the nape of the neck deep to the postvertebral muscles. Some days later, it tracks between the muscles and appears in the pos- terior triangle, close to the mastoid process. The mucous mem- brane of the roof of the nasopharynx may be torn, and blood may escape there.

Question 34

most common facial fractures

Answer 34

Fractures of the nasal bones, because of the prominence of the nose

Question 35

bones of vault form via

Answer 35

membranous ossification

Question 36

bones of the cranial base form via

Answer 36

endochondral ossification

Question 37

neonatal skull

Answer 37

no diploe
mobile bones
bones are separated by unossified membranous intervals called fontanelles
mastoid process is not present at birth and develops later in response to the pull of the sternocleid- omastoid muscle when the child moves his or her head
angle of the mandible at birth is obtuse

Question 38

structure susceptible to damage by forceps in a difficult delivery

Answer 38

facial nerve