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157 Cards in this Set

  • Front
  • Back
Which major cranial nerve that has only motor functions can be found in the posterior triangle of the neck?

Which muscles does it innervate?
CN XI – the spinal accessory nerve

SCM and the trapezius
Are the following structures primarily located in the anterior or posterior triangles of the neck?
a. Brachial plexus roots
b. Carotid arteries
c. Internal jugular vein
d. Hyoid bone
e. Scalene muscles
a. posterior
b. anterior
c. anterior
d. anterior
e. posterior
Which of the following are suprahyoid and which are infrahyoid muscles?
a. Mylohyoid
b. Geniohyoid
c. Stylohyoid
d. Digastric
e. Omohyoid
f. Sternohyoid
g. Sternothyroid
h. Thyrohyoid
a – d are suprahyoid
e – h are infrahyoid
Which vascular structure in the anterior neck functions as a baroreceptor?
the carotid sinus
Which structure in the anterior neck functions as a chemoreceptor?
the carotid body
Which nerve runs down the anterior border of the anterior scalene muscle?
the phrenic nerve
What are the 3 major components found within the carotid sheath?
carotid artery;
internal jugular vein;
vagus nerve (CN X)
What are the 2 major thyroid arteries and from where do they arise?
the superior thyroid artery - external carotid; and the

inferior thyroid artery - thyrocervical trunk off the subclavian
The isthmus of the thyroid gland usually lies immediately anterior to what structure?
the proximal trachea, just slightly below the cricoid cartilage anterior to the second and third tracheal rings
What percentage of people have a pyramidal lobe found on the thyroid gland?
about 50%
Which nerve is typically endangered during surgical removal or dissection of the thyroid gland?
the recurrent laryngeal nerve
What are the common names for the first and second cervical vertebrae?
atlas (C1) and axis (C2)
What artery travels through the foramina of the transverse processes of the cervical vertebrae?
the vertebral artery
Damage to what structure in the neck will produce Horner’s syndrome?
sympathetic nerves (chain)
What is the name of the functionally and clinically important potential space between the prevertebral fascia and the buccopharyngeal fascia (behind the pharynx)?
the retropharyngeal space
. Thoracic outlet syndrome refers to compression of the ________ ______ and/or __________ ______.
brachial plexus and/or subclavian artery
Where is the anterior fontanelle located?
Intersection of parietal and frontal bones

In the midline, at the intersection of the parietal and frontal bones – or at the junction of the sagittal , coronal, and metopic sutures (the metopic suture is the temporary suture between the two frontal bones which remain paired for a short period after birth).
The mastoid process is a feature of which cranial bone?
temporal bone
The styloid process is a feature of which cranial bone?
temporal bone
Which of the following are muscles of facial expression and which are muscles of
mastication?
a. Platysma
b. Orbicularis oris
c. Buccinator
d. Medial pterygoid
e. Masseter
f. Zygomatic major
g. Temporalis
a,b,c,f: facial expression -

d,e,g: mastication
Which cranial nerve innervates the muscles of facial expression?
CN VII – facial
which cranial nerve innervates the muscles of mastication?
CN V - trigeminal
Which cranial nerve is responsible for the sensory innervation of the face?
CN V – trigeminal
Which cranial nerve is damaged in the condition known as Bell’s palsy?
CN VII – facial
Which of the following arteries are not branches of the external carotid artery?
a. Facial
b. Lingual
c. Retromandibular
d. Occipital
e. Maxillary
f. Superior thyroid
g. Inferior thyroid
c – retromandibular is the name of a facial vein;

g – the inferior thyroid artery arises from the thyrocervical trunk, a branch of the subclavian artery.
By convention, how many layers of tissue make up the scalp? Which of these constitute the scalp proper?
5 layers;

1-3
In which layer of the scalp are the nerves and vessels located?
layer 2
Which layer of the scalp is known as the dangerous area ?
layer 4
In what anatomical region would you find the origin of the branches of the
maxillary artery?
the infratemporal fossa
In what anatomical region would you find the origin of the branches of the
mandibular nerve (V3)?
the infratemporal fossa
The parasympathetic fibers from the otic ganglion travel to which gland?
parotid gland
Which cranial nerve innervates the muscles that cause movement at the TM joint?
CN V- trigeminal. The muscles that move the TMJ are the muscles of
mastication.
Which cranial nerve can be found dividing into several branches inside the parotid
gland?
CN VII – facial
Which small space inside the skull is situated between the nasal cavity and the
infratemporal fossa?
the pterygopalatine fossa
Where would you find the palpebral portion of the orbicularis oculi muscles?
on the eyelids
As it travels from the parotid gland to the oral cavity, which muscle (of
mastication) does the parotid duct cross, and which muscle (of facial expression) does it pierce?
the duct crosses the masseter and pierces the buccinator.
What is the calvaria?
the upper domelike portion of the bony skull (the skullcap)
Where is the coronal suture?
in the coronal plane between the unpaired frontal bone and the
two parietal bones.
Where is the sagittal suture?
on the top of the skull between the two parietal bones.
Where is the pterion? Why is it a clinically important landmark?
an “H”-shaped sutural junction located on the lateral aspect of the skull.

junction of the greater wing of the sphenoid, the squamous temporal, the frontal, and the parietal bones.

it lies over the course of a large middle meningeal artery branch. Fractures across the pterion can lead to epidural hematomas.
Where would one find the middle meningeal artery? From what artery does it arise?
arises from the maxillary artery and enters the cranial cavity through the foramen spinosum. Its branches travel between the inside of the skull bones and the dura mater.
What type of hematoma typically results from tearing the middle meningeal artery?
Epidural hematomas
What cranial fossa contains the foramen magnum?
in the posterior cranial fossa.
What cranial fossa contains the superior orbital fissure?
in the middle cranial fossa.
What is the sella turcica? What important glandular structure is associated with it?
saddle-like prominence on the upper surface of the sphenoid bone,
situated in the middle cranial fossa and dividing it into two halves.

It contains the pituitary gland.
What is a gyrus? What is a sulcus?
one of the prominent rounded elevations that form the cerebral hemispheres.
The gyri are separated by sulci, which are the grooves or furrows on the surface of the
cerebrum.
Where is the pons located?
on the ventral surface of the brainstem between the midbrain and the
medulla oblongata, inferior to the cerebellum.
Where is the medulla oblongata located?
portion of the brainstem between the pons and the spinal
cord. It is continuous with the spinal cord at the foramen magnum.
What is the falx cerebri?
the sickle-shaped fold of dura mater in the longitudinal fissure
between the two cerebral hemispheres.
What would one find within the superior sagittal sinus?
contains venous blood. It also contains the arachnoid
granulations, which protrude into the sinus from beneath as the CSF pressure rises.
What is the predominant route by which cerebral blood drains from the cranial cavity?
The venous blood within the cranial cavity eventually collects in the larger cerebral veins
which drain into one of several dural venous sinuses. The blood in the dural venous
sinuses drains predominantly into the internal jugular vein.
What are emissary veins? Why are they clinically important structures?
Emissary veins are venous channels located between the venous sinuses of the dura
mater and the veins of the diploë and the scalp. They are clinically important in that they provide a potential passage for the spread of infection between the scalp and the intracranial venous sinuses.
Where is cerebrospinal fluid (CSF) produced?
CSF is produced within the ventricles of the brain by the choroid plexus.
What is the name of the structure that produces CSF?
Choroid plexus
How does the CSF eventually drain into the venous system?
The main passageway of CSF drainage is through the arachnoid granulations and into the
venous blood of the superior sagittal sinus.
What is hydrocephalus?
Hydrocephalus is any condition marked by an excessive accumulation of CSF within the
cranial cavity. One common type of hydrocephalus, caused by a congenital blockage of the cerebral aqueduct, results in dilation of the cerebral ventricles, thinning of the brain tissues and separation of cranial bones.
Which two pairs of major arteries enter the cranial cavity to supply blood to the brain?
The internal carotid arteries and the vertebral arteries.
What is the major unpaired artery that is formed from the two vertebral arteries within
the cranial cavity?
The basilar artery.
How do the anterior, middle, and posterior cerebral arteries arise?
The internal carotid arteries terminate within the cranial cavity by dividing into the anterior and middle cerebral arteries. The single basilar artery ends by dividing into two posterior cerebral arteries.
What is the Circle of Willis?
“circle” of arteries at the base of the brain,

the anterior communicating artery, the two anterior cerebral, the two internal carotid, the two posterior communicating, and the two posterior cerebral arteries.
How many pairs of cranial nerves are there?
There are 12 pairs of cranial nerves
What is the name of the seventh cranial nerve?
The seventh cranial nerve (CN VII) is the facial nerve.
What is the name of the tenth cranial nerve?
The tenth cranial nerve (CN X) is the vagus nerve.
What is the cranial nerve number of the glossopharyngeal nerve?
The glossopharyngeal nerve is CN IX.
Which cranial nerves travel through a foramen associated with the internal jugular vein?
CNs IX, X, and XI travel through the jugular foramen.
Which cranial nerves travel through the cribriform plate openings?
CN I travels through the cribriform plate.
Which cranial nerves travel through the superior orbital fissure?
CNs III, IV, V1, and VI travel through the superior orbital fissure.
In which cranial fossa is the internal auditory meatus located? Which cranial nerves
travel through it?
The internal auditory meatus, for CNs VII and VIII, is in the posterior cranial fossa.
Which cranial nerve has a component that travels through the foramen magnum?
CN XI (spinal accessory nerve) has a spinal root that travels through the foramen
magnum.
How do postganglionic sympathetic nerves get into the cranial cavity?
Sympathetic nerves enter the cranial cavity in a plexus on the major arteries traveling
from the neck into the cranial cavity – especially the internal carotid arteries.
What important glandular structure lies immediately inferior to the optic chiasm?
The pituitary gland lies immediately below the optic chiasm.
Which unique cranial nerve structure lies within the Circle of Willis?
The optic chiasm of CN II lies within the Circle of Willis.
Where is the cavernous sinus located?
The cavernous sinuses are located on either side of the sella turcica in the middle cranial
fossae.
Which artery travels directly through the cavernous sinus?
The internal carotid arteries travel through the cavernous sinus.
How is the eyelid elevated and closed? What nerves are responsible for this movement?
OPEN - Levator palpebrae superioris muscle (CN III) contracts and elevates the eyelid (attached to tarsal plate).

CLOSE - Contraction of the palpebral fibers of the orbicularis oculi muscle (CN VII) (and gravity).
Where are tears produced and how do they travel to the nasal cavity? What structures do they
pass through?
Stimulation of the lacrimal gland (parasympathetic fibers from facial) - flow through small ducts and enter the upper outer fornix area of the eye.

Conjunctiva, eyelid, superior/inferior puncta (exit) in lacrimal papillae (eyelids), small canaliculi, lacrimal sac, nasolacrimal duct, inferior meatus (nose)
What are the conjunctiva, sclera, cornea, iris, lens, and pupil of the eye?
conjunctiva - mucous covering of the eyeball and inner surface of the eyelid.

sclera - connective tissue layer that makes up the wall of the eyeball (white of the eye) and is continuous with the cornea

cornea - clear layer through which light enters the bulb.

iris the diaphragm at the front of the eyeball

lens - sits just behind iris and changes shape to focus the light on the retina.

pupil - the opening adjusted by movement of the iris.
What muscles either singly or together act to move the eye up, down, medially, and laterally?
Medial movement – medial rectus muscle;

lateral movement – lateral rectus muscle;

movement up – superior rectus and inferior oblique muscles;

movement down – inferior rectus and superior oblique.
What nerves innervate these muscles?
Superior oblique – trochlear (CN IV); Lateral rectus - abducens (CN VI); all other oculomotor (CN III)
What are the layers of the eyeball? What is the ciliary body?
outer - sclera and cornea.

middle - choroids, ciliary body, ciliary processes, and iris.

inner - retina.

The ciliary body is an anterior thickening of the middle layer containing muscles which control the shape of the lens, movement of the iris and serves as a point of attachment for suspensory ligaments of the lens.
What is the function of the retina?
translates light into neural impulses for transmission through the optic nerve to the optic centers of the brain.
Where vision is the most acute? What is the blind spot?
fovea

The blind spot is the optic disc where the optic nerve and ophthalmic vessels enter the eyeball.
How the blood is distributed to the orbit and eyeball?
Blood enters the posterior of the orbit in the ophthalmic artery (branch of the internal carotid) through the optic foramen with the optic nerve. It then travels somewhat medially giving off branches to the posterior of the eyeball, the muscles and then ending with superior and medial branches. It also gives off the central artery of the retina that travels through the center of the optic nerve to emerge at the optic disc.
What are the major branches of the ophthalmic division of the trigeminal nerve in the orbit?
Frontal with supraorbital and supratrochlear branches;
lacrimal;
nasociliary.
What nerve is sensory to the cornea?
The ophthalmic division of the trigeminal by way of the branches from the nasociliary
How does the iris open and close? What muscles and nerves are responsible?
OPEN - radial muscles, dilator pupillae, innervated by postganglionic sympathetic fibers from the cervical sympathetic trunk.

CLOSE - circular sphincteric fibers, sphincter pupillae, innervated by parasympathetic fibers from the oculomotor nerve. These postganglionic parasympathetic fibers originate in the ciliary ganglion posterior to the eyeball.
How does the lens changes shape? What muscle and nerve is responsible?
Stretched into an elongated shape by tension on the suspensory fibers that connect it to the ciliary body. FAR VISION

Contraction of the ciliary muscle in the ciliary body releases that tension and allows the lens to become rounded, NEAR VISION

CN III
What structures focus light on the retina?
cornea, lens (adjustable) , and to a lesser extent by the vitreous humor.
What is relationship of the facial vein and the venous drainage in the orbit?
The ophthalmic vein drains from the posterior orbit through the superior orbital fissure and then into the cavernous sinus. However it has numerous connections anteriorly with the facial vein. Thus it is possible for infection to travel from the facial vein into the ophthalmic vein and then to the cavernous sinus where it can expand and in some cases cause meningitis.
What are the openings in the posterior wall of the orbit and what passes through them?
Optic foramen – optic nerve, ophthalmic artery;

Superior orbital fissure – oculomotor, trochlear, abducens, and trigeminal (ophthalmic division), and ophthalmic vein.
What cranial nerves are found in the eye and orbit and in general what they do (Hint: CNII,
CNIII, CNIV, CNV, CNVI, CNVII)?
Optic nerve (CN II) – vision.

Oculomotor nerve (CN III) – movement of muscles of the eye, parasympathetic fibers to the muscles in iris and ciliary body.

Trochlear nerve (CN IV) – motor nerve to the superior oblique muscle.

Trigeminal nerve (CN V) – ophthalmic division V1 is sensory to the skin over the orbit, the surface of the eyeball and cornea.

Abducens nerve (CN VI) – motor nerve to the lateral rectus muscle.

Facial nerve (CN VII) – small branch that provide parasympathetic fibers to stimulate the lacrimal gland to secrete, motor nerves to the orbicularis oculi.
Will patients with head trauma be more likely to receive plain X-ray imaging or CT imaging?
CT imaging
What 2 different “windows” are used in CT imaging?
bone window and soft tissue window
Which of the following can be readily imaged with CT scans of the cranium? a. Optic canal
b. Foramen rotundum c. Foramen ovale d. Internal acoustic meatus e. Jugular Foramen
All of the above
What advantage does MRI provide when imaging the skull and CNS?
MRI usually provides much better resolution of the brain and spinal cord tissues than other imaging modalities. Also, many types of CNS pathology can be better visualized with MRI.
In which MRI mode will the CSF be dark?
T1
What mode of MRI is most useful in visualizing CNS pathology related to
hemorrhagic bleeding?
T2
Name three imaging methods used to gain information about the function or
functional states of different regions of the brain.
F-MRI; PET; SPECT
Of the methods that are the answers to the previous question, which require the
use of radioactive compounds?
PET; SPECT
What component of blood does F-MRI make use of to generate images?
the
iron in the hemoglobin molecules.
where the auditory (Eustachian) tube opens. What structure surrounds this opening?
Into the lateral wall of the nasopharynx just posterior to the nasal cavity.

The torus tubarius is a cartilage tube-like structure that creates a rounded elevation around the opening that helps maintain patency of the auditory tube.
where the sinuses surrounding the nasal cavities are located and where they drain.
Frontal sinuses are found in the frontal bone anteriorly – drain through frontonasal duct to the middle meatus at the anterior hiatus semilunaris.

Ethmoid sinuses in the ethmoid bulla and upper lateral nasal area – they drain through numerous small openings into the middle meatus and some posterior ones into the superior meatus.

Sphenoid sinuses are in the body of the sphenoid bone posterior superior to the nasal cavity – drain to the space above the superior conchae (sphenoethmoidal recess).

Maxillary sinus in each maxillary bone lateral to the nasal cavity – drain to the middle meatus at the posterior hiatus semilunaris.
how the maxillary sinus is different.
Opening is in the superior aspect of the sinus - mucus must be directed upward by the ciliated epithelium to the opening.

Difficult to drain when the sinus is filled and the individual is upright.

Roots of the teeth form conical elevations that protrude into the floor of the sinus, thus infections at the roots of the teeth can penetrate into the sinus cause complications.
what other major structures are related to the maxillary sinus.
The orbit is separated from the sinus by a thin sheet of bone. The close proximity of teeth to the floor of the sinus is also important.
what nerves innervate the walls of the nasal cavity
The maxillary division of the trigeminal nerve (CN V2) provides branches to the mucosa through nasal branches and the nasopalatine nerve that supplies the nasal septum.

The upper portion of the nasal cavity is supplied by olfactory nerves that penetrate the cribriform plate from the olfactory bulbs.
what nerves stimulate mucous secretion in the nasal cavity.
Parasympathetic fibers (facial nerve (CN VII) through its greater petrosal branch as preganglionic fibers. - pterygopalatine ganglion - maxillary nerve in the pterygopalatine fossa - postganglionic parasympathetic fibers (w/ branches of the maxillary) to the nasal mucosa AND w/ greater and lesser palatine nerves to the surface of the hard and soft palates.
where the blood supply to the nasal cavity originates.
branches of the sphenopalatine artery (continuation of the maxillary artery).

They enter the posterior area of the nasal cavity and spread anteriorly.
what muscles are associated with the soft palate and what they do.
(3 muscles)
levator veli palatini + tensor veli palatini.

levator veli palatini - elevates the soft palate or increases its curvature

tensor palatine - tenses the palate and flattens it.

palatopharyngeus - helps tense the palate and pulls up on the walls of the pharynx effectively narrowing the opening between the oropharynx and nasopharynx.
what are the three areas of the pharynx.
nasopharynx, oropharynx, and laryngopharynx.
what is the function of the pharyngeal constrictors.
The pharyngeal constrictors (superior, middle, and inferior) contract involuntarily in a superior to inferior pattern such that the sequential constriction helps propel food into the opening of the esophagus.
what innervates the wall of the pharynx.
pharyngeal plexus - pharyngeal branches of the vagus (CN X) and contributions from the spinal accessory (CN XI) nerves.

These include motor fibers to muscles of the wall of the pharynx (and sensory fibers from the vagus).
where the major tonsilar structures are located.
ring-like manner around the openings of the naso- and oropharynx into the alimentary tract.

The pharyngeal tonsils (adenoids if inflamed) are located adjacent Eustachian tube openings on the lateral wall of the nasopharynx

palatine tonsils are located on the lateral walls of the oropharynx

lingual tonsils are found on the posterior surface of the tongue.
what two bones are primarily responsible for side-to-side movement of the skull, nodding of the head.
Side to side movement is due to the articulation of the atlas and axis.

Nodding (flexion-extension) is due to the articulation of the occipital bone of the skull with the atlas.
what the alar (check) ligament does.
connects the dens with the occipital bone

limits rotation of the skull on the vertebral column.
what the dens (odontoid process) does and what holds it in place.
It forms the point of rotation of the atlas on the axis.

Held in place by the transverse fibers of the cruciate ligament.
what the space is between the cervical vertebral bodies and the posterior pharyngeal wall, and its clinical significance.
The retropharyngeal space lies between the prevertebral and buccopharyngeal fascias of the neck.

It is a potential route for spread of infection from the deep neck structures into the superior mediastinum.
where the valleculae, vestibule, and piriform recesses are located.
valleculae - spaces located on either side of the midline posterior to the tongue and anterior to the epiglottis.

piriform recess - the space in the laryngopharynx just posterior to the larynx between the thyroid cartilage and the aryepiglottic fold.

vestibule - the space posterior to the epiglottis between the aryepiglottic folds and above the false vocal folds. It is the entryway to the respiratory tract.
the pathway for food material as it passes to the esophagus without passing into the
airway.
posterior surface of the tongue as it is swallowed and into the valleculae - passes to either side of the epiglottis - into the piriform recesses - enters the upper portion of the esophagus.
what is the narrowest part of the airway and where is it located.
rima glottidis,

the space found between the true vocal cords (vocal ligaments).

changes shape when speaking, coughing, or breathing heavily.
what nerves innervate the mucosal surface of the larynx and where they originate.
The mucosal surface down to the level of the vocal cords is innervated by the internal laryngeal branch of the superior laryngeal nerve. The mucosa up to the level of the vocal cords is innervated by branches of the inferior (recurrent) laryngeal nerve. Both laryngeal nerves are derived from the vagus nerve.
what composes the laryngeal skeleton (cartilages). How do these cartilages articulate
with one another?
thyroid cartilage, cricoid cartilage, the epiglottis, and the arytenoid cartilages.

The thyroid cartilage and cricoid cartilage articulate with one another laterally

arytenoid cartilages articulate with the upper posterior surface of the cricoid.
where the thyrohyoid, cricothyroid, and quadrangular membranes are located and how they
shape the laryngeal complex.
thyrohyoid membrane - stretching between the thyroid cartilage and the hyoid bone - internal laryngeal nerve and superior laryngeal artery.

cricothyroid membrane - thyroid and cricoid cartilages

quadrangular membrane - epiglottis to the aryteoid cartilages. - inferior margin helps form the false vocal fold - helps form the backing for the wall of the vestibule.
the muscles that change the position and tension of the vocal cords, how this is accomplished,
and what nerve innervates them.
recurrent laryngeal nerve

The vocal cords are (adduct) or separated (abduct) by the movement of the vocal process or stretched (tensed) by the movement of the cricoid and thyroid cartilages.

Abduction of cords – posterior cricoarytenoid muscle.
Adduction of cords – lateral cricoarytenoid, arytenoids.
Stretch vocal cords – cricothyroid muscle.
understand when the vocal cords are opened and closed. Why are they closed to cough?
The vocal cords are closed when attempting to increase intra-thoracic and/or intra-abdominal pressure or just prior to coughing.

They are opened slightly when producing sound for speaking, opened slightly wider for normal breathing, and opened very wide during forced respiration.
know how sound is produced.
Sound is produced when the vocal cords (or ligaments) are approximated, and air is moved from the thoracic cavity through the narrow gap between them, the rima glottides.

Movement of air causes the cord to vibrate which produces sounds.

The pitch is changed as a result of contraction of the vocalis muscle that changes the tension along the cords.

The sound produced is then modified by the mouth, tongue, lips, etc.
know the difference between true and false vocal folds. What is found between them?
True vocal cords - where sound is actually produced

space between = rima glottids

The space between the true and false vocal folds is known as the ventricle.
where is the vocal ligament or cord is located.
The actual vocal cord or ligament is located at the free medial edge of the fold so that it is exposed to the air rushing by and can therefore vibrate.
what is the function of the vocalis muscle.
The vocalis muscle is the midline fibers or portion of the larger thyroarytenoid muscle. It is responsible for altering the tension of the vocal ligament and thus changing the pitch of the voice.
why damage to the inferior laryngeal nerves is important.
The inferior laryngeal nerves control movement of the intrinsic muscles of the larynx. Therefore damage to the nerve results in muscle malfunction and loss of control of air movement and, of course, voice.
what happens if only one nerve is damaged.
Damage to only one nerve results in impaired movement of cords on one side resulting in hoarseness.
how the Heimlich maneuver works and review what is done during a cricothyrotomy.
Foreign objects often lodge in the vestibule just above the vocal folds. During the Heimlich maneuver the thoracic cavity is squeezed quickly, increasing thoracic pressure and forcing air up against the lodged object. Hopefully enough pressure is exerted that the object is moved out of the airway and the air can begin moving back and forth in normal respiration. Remember a cricothyrotomy is done to open an airway in an emergency. The airway is very close to the surface at the level of the vocal cords. It is separated from the outside only by the thickness of the skin and the cricothyroid membrane. These are incised and a hollow object is placed in the opening to maintain patency and allow air to move in and out. This position is usually below the level of the blockage so air movement can take place.
What is the vestibule of the mouth?
1. The oral vestibule is the space between the lateral surfaces of the teeth (and gums) and the inside of the cheeks and lips.
2. How many permanent teeth are there? deciduous teeth?
32, 20
3. Branches from which cranial nerve provide sensation to the upper and lower teeth?
3. Trigeminal (CN V). V2 supplies branches to the upper teeth, V3 branches to the lower teeth
4. Which muscle of the palate is innervated by CN V?
4. Tensor veli palatini m.
5. Which muscle of the palate appears to emerge from the auditory tube opening in the nasopharynx?
5. Levator veli palatini m.
6. Which cranial nerve provides taste sensation to the taste buds in the circumvallate papillae and posterior 1/3 of the tongue? general sensation?
Glossopharyngeal (CN IX) provides taste sensation to the circumvallate papillae and general sensation to the posterior 1/3.
7. Which cranial nerve innervates virtually all the muscles of the tongue?
Hypoglossal (CN XII) innervates every tongue muscle except the palatoglossus.
8. Which cranial nerve provides taste sensation to the anterior 2/3 of the tongue?
Facial (CN VII) through the chorda tympani branch (that travels with the lingual n. from V3)
9. Which cranial nerve provides general sensation to the anterior 2/3 of the tongue?
Trigeminal (mandibular branch - CN V3) via the lingual nerve
1. What is the major artery that supplies blood to the tongue? From what artery does it arise?
The lingual artery – a branch of the external carotid.
10. Which salivary glands have ducts that pierce the buccinator muscles?
On each side of the face, the duct of the parotid gland pierces the buccinator m.
11. Which salivary glands have ducts that open on either side of the frenulum of the tongue?
The submandibular glands
12. What structure lies between the palatoglossal and palatopharyngeal folds?
The tonsil (or palatine tonsil)
13. How can you determine if the right hypoglossal nerve is damaged?
If the right hypoglossal nerve is damaged, the protruded tongue will deviate to the right.
1. What are the major features of the medial and lateral ‘walls’ of the middle ear?
The lateral wall is made up primarily of the tympanic membrane and the structures attached to it such as the chorda tympani nerve. The medial wall is composed primarily of the promontory, which is covered by fibers of the tympanic plexus. It also has two small openings, the oval window where the footplate of the stapes is inserted, and the round window sealed with a thin membrane. The promontory is the bulge formed by the first turn of the cochlea of the inner ear.
2. In which bone is the middle ear located?
The petrous portion of the temporal bone.
3. What are the mastoid air cells and why they are important?
The mastoid air cells are
airspaces lined with mucosa that occupy the mastoid process of the temporal bone. They are connected with each other and are continuous with the middle ear cavity at the aditus to the mastoid antrum. The antrum is an enlarged space into which the air cells open. The cells are important since a middle ear infection (otitis media) may spread to these spaces where the infection can proliferate and access is limited. They can thus act as a reservoir of infection.
4. What is the roof of the tympanic cavity and what structure is close to it?
tegmen tympani.

It is relatively thin and is adjacent to the dural lining of the cranial cavity.

Infection can erode through the tegmen and then can spread to and through the meningial lining causing meningitis.
5. What are the openings into the middle ear cavity?
The openings to the cavity are the auditory or pharyngotympanic tube anteriorly and the aditus to the mastoid antrum posteriorly.
6. What are the ossicles and how do they function?
The ossicles are the malleus, incus, and stapes.

They articulate with one another, and transmit movement to the cochlea of the inner ear.
What muscles dampen movement of the ossicles? Why is that important?
The tensor tympani is attached by a tendon to the handle of the malleus. - V3

The tendon of the stapedius extends out of the apex of the pyramid which enclosed the stapedius muscle and attaches to the stapes. - VII

When these muscles contract they reduce the movement of the ossicles and thus reduce the amplitude of transmission and dampen the sound transmitted to the inner ear. This is a reflex function that helps protect the auditory apparatus from excessive noise and subsequent damage.
What is the function of the tympanic membrane, what structures cross it? How does the
membrane change with a middle ear infection?
vibrates with the sound pressure waves that hit it.

transmits that movement into movement of the ossicles - convey the sound energy to the inner ear where it is translated.

chorda tympani nerve from the facial nerve (VII) crosses the upper inner surface of the tympanic membrane. Damage to this portion of the middle ear can damage the nerve, which interferes with the taste function of the anterior 2/3 of the tongue.

ear infections (otitis media) - tympanic membrane will become reddened and the presence of fluid in the tympanic cavity behind the membrane will cause it to change shape - change in the light reflective character of the membrane - no longer being able to see the ‘cone of light’ present on a normal membrane.

pain or discomfort due to irritation of the sensory nerves of the cavity.
9. What is the auricle?
external ear structure - collects sound and funnels it into the external meatus - contacts the tympanic membrane
10. Where is sound converted to neural impulses in the ear?
inner ear.

Movement of the footplate of the stapes - movement of fluid in the turns of the cochlea of the middle ear - sensed by neural cells within the cochlear duct - transmit signals to the brain via the vestibulocochlear nerve (CN VIII)
11. What are the main functions of the inner ear?
hearing

detection of the position of the head in space

balance (semicircular canals),

movement, i.e., acceleration and deceleration.
12. What is otitis media? What are the two types of hearing loss?
inflammation and accumulation of fluid within the tympanic cavity caused in many cases by the closure or swelling of the musosa of the auditory tube.

1) Conductive - due to impaired movement of the ossicles or damage to the tympanic membrane and thus interference with transmission of the sound energy to the inner ear.

1) sensorineural loss - due to problems within the cochlea, the nerve cells there, or within the brain.