Cross Sectional Anatomy Chapter 2 Cranium and facial bones

• Differentiate between the three cranial fossae. • Identify the location and unique structures of each cranial and facial bone. • Identify the structures of the external, middle, and inner ear, and describe their functions. • Identify the cranial sutures. • Describe the six fontanels in the infant cranium. • Describe the structures that constitute the temporomandibular joint. • Identify the location of each paranasal sinus and the meatus into which it drains. • Identify the structures of the osteomeatal unit. • Identify the bones that form the orbit and their associated openings. • Describe the structures that constitute the globe of the eye. • List the muscles of the eye, and describe their functions and locations.

What is A

Sella turcica

What is B

Dorsum sella of sphenoid bone

What is C

Squamous portion of occipital bone

What is D

Occipital bone

What is E

Posterior arch of C1

What is F

Clivus of occipital bone

What is G

Sphenoid sinus

What is H

Ethmoid sinuses

What is I

Tuberculum sella

Parietal

Sides of the cranium

Occipital

Clivus

Frontal

Orbital plate

Temporal

Carotid canal

Sphenoid

Foramen ovale

Ethmoid

Cribriform plate

The largest immovable facial bone is the mandible.

True or False

False

The temporomandibular joint (TMJ) is formed by the condyloid process, the mandible, and the mandibular fossa of the temporal bone.

True or False

True

The maxillary sinuses drain into the inferior nasal meatus.

True or False

False

There is typically only one sphenoid sinus.

True or False

False

The ethmoid bulla is part of the osteomeatal unit.

True or False

True

The inner ear is normally fluid filled.

True or False

True

The vestibule is a structure of the inner ear that controls hearing.

True or False

False

The temporal bone forms part of the bony orbit.

True or False

False

The lacrimal gland is located in the inferior medial portion of the orbit.

True or False

False

A function of the oblique muscle group is to rotate the eyeball.

True or False

True

Located within the basilar turn of the cochlea is the ____.

Round window

The ______ is located at the junction of the brainstem and spinal cord.

Foramen magnum

The basilar portion of the occipital bone is termed the ____.

Clivus

The zygomatic process extends form the ____ bone.

Temporal

The ______ bone is shaped like a butterfly and extends across the entire floor of the middle cranial fossa.

Sphenoid

Located on the lateral surface of the ramus is the _____ muscle, which elevates the mandible.

Masseter

The _____ forms the inferior portion of the bony nasal septum.

Vomer

The ______ creates the anterior boundary of the temporomandibular joint, preventing forward displacement of the mandibular condyle.

Articular eminence

The ethmoid notch of the frontal bone articulates with the ______ of the ethmoid bone.

Cribriform plate

The anterior portion of the sella turcica is termed the _____.

Tuberculum sellae

One of the largest of the ethmoid air cells (ethmoid sinuses) is the ____.

Ethmoid bulla

The greater wings of the sphenoid bone contain three paired foramina termed the ____, and ____.

Rotundum ovale, spinosum

The articular disk of the TMJ is attached to the medial and lateral surface of the mandibular condyle by the ____.

Collateral ligaments

Ethmoid: anterior

Drainage Location

Middle nasal meatus

Ethmoid: posterior

Drainage Location

Superior nasal meatus

Maxillary

Drainage Location

Middle nasal meatus

Sphenoid

Drainage Location

Sphenoethmoidal recess

Frontal

Drainage Location

Middle nasal meatus

The largest immovable facial bone is the maxilla.

True or False

True

The maxillary sinuses drain into the middle nasal meatus

True or False

True

The sphenoid sinuses are typically paried and separated by a septum.

True or False

True

The vestibule is a part of the inner ear, but it is involved with balance and equilibrium.

True or False

True

The bony orbit is composed of the frontal, sphenoid, and ethmoid bones of the cranium and the lacrimal, palatine, maxillary, and zygoma of the facial bones.

True or False

True

The lacrimal gland is located in the superior lateral portion of the orbit.

True or False

True

Describe the superior orbital fissure.

located between the lesser and greater wings of the sphenoid bone in a triangular opening, for the passage of the oculomotor, trochlear, abducens, and ophthalmic division of the trigeminal nerves as well as the ophthalmic veins.

Describe the mastoid antrum.

located on the anterosuperior portion of the mastoid process. It is an air-filled cavity that communicates with the middle ear (tympanic cavity)

List the structures of the middle ear.

consists of the tympanic membrane and the three auditory ossicles ( malleus, incus, and stapes.)

List the structures of the inner ear, and describe their function.

The inner ear contains the vestibule and semicircular canals, which control equilibrium and balance, and the cochlea, which is responsible for hearing.

List the cranial bones that are joined together by the squamous suture.

The squamous portion of the temporal bone to the parietal bone.

Describe the anterior fontanel.

Termed bregma and is located at the junction of the upper parietal and frontal bones. This fontanel remains open until age 2.

Describe the parts of the hard palate.

The anterior three-fourths of the hard palate is formed by the palatine process of the maxilla, and the posterior one-fourth is created by the horizontal portion of the palatine bones.

Describe the anterior and posterior compartments of the globe of the eye and what each compartment contains.

The anterior compartment is a small cavity located anterior to the lens. It contains the cornea and iris and is filled with aqueous humor, which helps maintain infraorbital pressure. the larger posterior compartment is located behind the lens and is surrounded by the retina. The posterior compartment contains vitreous humor, which helps maintain the shape of the eyeball.

Which cranial bones form the largest portion of the sides of the cranium?

Parietal bone

Which cranial bone contains the superior and middle nasal conchae?

Ethmoid bone

The foramen rotundum is contained in which cranial bone?

Sphenoid bone

The optic canal is separated form the superior orbital fissure by which of the following?

Optic strut

Which cranial bone contains the hypoglossal canal?

Occipital bone

Which of the following foramina is a jagged slit that allows the internal carotid artery to enter the cranium and is located between the apex of the petrous pyramid, body of the sphenoid bone, and basilar portion of the occipital bone?

Foramen lacerum

The region surrounding the sphenoparietal suture where the parietal, sphenoid, temporal, and frontal bones meet is termed the:

Pterion

The anterior nasal spine is part of which facial bone?

Maxillary

Which part of the mandible contains the alveolar process?

Body

Which of the following muscles is the strongest muscle of the jaw, arising form the zygomatic arch and inserting on the ramus and angle of the mandible?

Masseter

What is A

Superior rectus muscle

What is B

Optic nerve

What is C

Inferior rectus muscle

What is D

Maxillary sinus

What is E

Inferior oblique muscle

What is F

Retroorbital fat

What is G

Lens

What is H

Globe

What is A

Anterior fontanel (bregma)

What is B

Sagittal suture

What is C

Coronal suture

What is D

Frontal (metopic suture)

What is A

Frontal bone

What is B

Meningeal vessel

What is C

Vertex

What is D

Meningeal vessels

What is E

Internal table

What is F

Diploe

What is G

External table

What is H

Occipital bone

What is I

External occipital protuberance

What is J

Internal auditory canal

What is K

Dorsum sella

What is L

Sella turcica

What is M

Anterior clinoid process

What is N

Vomer

What is O

Sphenoid bone

What is P

Ethmoid bone

What is Q

Nasal bone

What is R

Frontal sinus

What is S

Crista galli of ethmoid bone

What is A

Lateral pterygoid muscle

What is B

Medial pterygoid muscle