Cerebral Cranium/Cranial Bone

Question 1

This single bone forms the
forehead and part of the roof of the
skull.
• It’s smooth part forms the
forehead;
• It’s orbital parts form the roof
of the orbits;
• And nasal parts help to form
the nasal cavities.

Answer 1

Frontal bone

Question 2

Are the ridges forming the upper margins of the circular
openings of the orbits.

Answer 2

Supra orbital borders/ supra orbital margin

Question 3

Is a smooth, rounded bony prominence above
the nose.
It lies between the supra-orbital borders of the
frontal bone.

Answer 3

GLABELLA

Question 4

Are paired cavities in the squamous or
forehead part of the frontal bone, one on each
side. They communicate with the nose and vary in
size and/or maybe absent.

Answer 4

Fontal sinuses

Question 5

Is the middle point of the Fronto-Nasal suture.

Answer 5

Nasion

Question 6

Lies towards the medial end of each supra-orbital border
allowing blood vessels and nerves to pass.

Answer 6

Supra orbital notch/supra orbital foramen

Question 7

Are paired bones, one on each side of the Cerebral
Cranium.

Answer 7

Parietal bones

Question 8

is a bony prominence on the outer surface of each parietal bone
which is the greatest transverse diameter of the skull.

Answer 8

Parietal eminence

Question 9

Is a single bone which forms the posterior part as
well as the part of the base or floor of the cerebral cranium.

Answer 9

Occipital bone

Question 10

Enumerate the 5 parts of frontal bone

Answer 10

-Supra orbital borders/supra orbital margin
-glabella
-frontal sinuses
-nasion
-supra orbital notch/supra orbital foramen

Question 11

Is the flat posterior part of the occipital bone.

Answer 11

Squamous part

Question 12

is an opening in the lower part of the
occipital bone through which the Medulla of the brain leaves the
skull, which is formed entirely by the occipital bone.

Answer 12

Foramen Magnum

Question 13

lie on each side of the
Foramen Magnum.

Answer 13

Lateral parts of the occipital bone

Question 14

– are two oval
prominences on the under surface of the
lateral parts of the foramen magnum
- form the joints with the superior
articular surfaces of the first cervical
vertebra or Atlas.

Answer 14

Occipital condyles

Question 15

part in front of the Foramen
Magnum which unite with the Sphenoid bone in front and
forms part of the floor of the skull.

Answer 15

Based of the occipital bone

Question 16

– is the bony prominence on the outer
surface of the squamous part of the occipital bone which is
readily palpable.

Answer 16

External occipital protuberance/innion

Question 17

Enumerate the parts of occipital bone

Answer 17

-squamous part
-foramen magnum
-occipital condyles
-lateral part of the occipital bone
-based of the occipital bone
-external occipital protuberance/innion

Question 18

Forms part of the lateral walls and base of the skull.

Answer 18

Temporal bone

Question 19

is a slender bony process
that extends forward from the squamous part
to meet a similar process of the Zygomatic bone
forming the “Zygomatic Arch”

Answer 19

Zygomatic process

Question 20

is a large rounded bony
prominence extending down behind the ear.

Answer 20

Mastoid process

Question 21

are small cavities in the
mastoid process and adjacent part that
communicate with the middle ear

Answer 21

Mastoid air cells

Question 22

Infection in the middle ear may spread into these cells

Answer 22

Mastoiditis

Question 23

is shaped like a pyramid that extends from
the ear medially and forward in the base of the skull. Its inner
end is pointed and contains the organ of hearing.

Answer 23

Petrous part

Question 24

is a sharp pointed process that extends
down from the base of the petrous part which is seen in
lateral view of the skull outlined behind the mandible. It is an
attachment point for muscles and ligaments of the neck

Answer 24

Styloid process

Question 25

– a tube-like passage extending into the petrous part of the temporal bone.

Answer 25

External auditory meatus

Question 26

lies in the middle or inner part of the petrous, medial to the middle ear

Answer 26

Internal auditory meatus

Question 27

lies in the petrous part and is the organ of hearing.

Answer 27

Internal ear

Question 28

a depression on the temporal bone in front of the EAM.

Answer 28

Mandibular/ articular fossa

Question 29

– is an opening medial to the styloid process through which the internal jugular vein and cranial nerves IX, X and XI pass.

Answer 29

Jugular foramen

Question 30

is an opening medial to the styloid process through which the internal carotid artery passes into the cranial cavity.

Answer 30

Carotid canal

Question 31

is a tiny opening between the mastoid and Styloid processes through which cranial nerve VII leaves the cranium.

Answer 31

Stylomastoid foramen

Question 32

is an opening between the petrous temporal bone and the sphenoid providing passage for a number of small nerves and for the internal carotid artery to enter the middle cranial fossa.

Answer 32

Foramen lacerum

Question 33

What are the parts of temporal bones?

Answer 33

Zygomatic process Mastoid process Mastoid air cella Petrous parts Styloid process External auditory meatus Internal auditory meatus Internal aer Mandibular/ articular fossa Jugular foramen Carotid canal Stylomastoid foramen Foramen lacerum

Question 34

A single bone that help to form a small part of the lateral wall of the skull on each side as well as part of the base of the skull. It is compared to a Bat with two pairs of wings extended.

Answer 34

Sphenoid bone

Question 35

is the central part that lies in the midline of the floor of the skull, in front of the occipital bone.

Answer 35

Body

Question 36

extended laterally from the body.

Answer 36

Wings

Question 37

are two cavities within the body of the bone, one on each side of the midline that lie behind the nasal fossae and open into them.

Answer 37

Sphenoid sinuses

Question 38

is an opening at the front on each side of the body of the sphenoid.

Answer 38

Optic foramen

Question 39

is a depression hallowed out on the upper surface of the body which is shaped like a saddle wherein the Pituitary gland/ Hypophysis lies in this depression.

Answer 39

Sella turcica

Question 40

Is the posterior wall of the Sella Turcica where it curve upward like the back of a saddle.

Answer 40

Dorsum sella

Question 41

are two small rounded bony processes that extend up and forward from the top of the Dorsum Sella.

Answer 41

Posterior clinoid processes

Question 42

are two similar processes that extends back from the lesser wings of the sphenoid over the Sella Turcica.

Answer 42

Anterior clinoid processes

Question 43

WHAT ARE THE PARTS OF THE SPHENOID BONE

Answer 43

body Wings Pterygoid process/plates Sphenoid sinuses Optic foramen Sella turcica Dorsum sella Posterior clinoid processes Anterior clinoid processes

Question 44

Lies in the anterior part of the base of the skull between orbits. Like the Sphenoid bone, this bone is only partly visible because of the adjacent bones.

Answer 44

Ethmoid bone

Question 45

it fills in a small gap between the orbital parts of the frontal bone.

Answer 45

Cribriform plate

Question 46

is a sharp flat pointed process that extends up from the cribriform plate in the midline wherein the Falx Cerebri is attached to it.

Answer 46

Crista galli

Question 47

is a thin, flat, downward extension from the cribriform plate that forms a part of the nasal septum.

Answer 47

Perpendicular plate

Question 48

are many small cavities in the labyrinth on each side.

Answer 48

Ethmoid sinuses

Question 49

What are the parts of ethmoid bone

Answer 49

Cribriform plate Crista galli Perpendicular plate Ethmoid sinuses