Introduction to the Cranial Nerves

Question 1

___ sets of cranial nerves exit foramina of the skull

like the spinal nerves, they are part of the ___ system

by convention, they’re designated by roman numerals ___a

Answer 1

12

peripheral nervous

I - XII

Question 2

cranial nerve I (___) is associated w/ the ___

cranial nerve II (___) develops from the ___

all the rest are associated w/ the ___

Answer 2

olfactory
telencephalon

optic
diencephalon

brainstem

Question 3

midbrain cranial nerves (2)

Answer 3

CN III (oculomotor)
CN IV (trochlear)

Question 4

pons cranial nerves (4)

Answer 4

CN V (trigeminal)
CN VI (abducens)
CN VII (facial)
CN VIII (vestibulocochlear)

Question 5

medulla oblongata cranial nerves (4)

Answer 5

CN IX (glossopharyngeal)
CN X (vagus)
CN XI (accessory)
CN XII (hypoglossal)

Question 6

cranial nerves III, VII, IX, & X contain (preganglionic/postganglionic) (sympathetic/parasympathetic) fibers

Answer 6

preganglionic

parasympathetic

Question 7

the cell bodies of all general sensory neurons (___ neurons) are located in the ganglia of the following cranial nerves (4)

Answer 7

pseudounipolar

(V) trigeminal nerve
(VII) facial nerve
(IX) glossopharyngeal nerve
(X) vagus nerve

Question 8

the cell bodies of taste neurons (___ neurons) are located in the ganglia of the following cranial nerves (3)

Answer 8

pdeudounipolar

(VII) facial nerve
(IX) glossopharyngeal nerve
(X) vagus nerve

Question 9

the cell bodies of motor neurons (___ neurons) are located in separate & discrete units called ___ within the ___

Answer 9

multipolar
nuclei
brainstem

Question 10

the ___ nerves innervate all of the structures derived from the branchial arches

Answer 10

branchiomeric cranial

Question 11

the branchiomeric cranial nerves innervate all of the structures derived from the ___

Answer 11

branchial arches

Question 12

branchiomeric cranial nerves & corresponding branchial arches (5)

Answer 12

trigeminal nerve (V) - branchial arch 1
facial nerve (VII) - branchial arch 2
glossopharyngeal nerve (IX) - branchial arch 3
vagus nerve (X) - branchial arches 4-6
accessory nerve (XI) - branchila arches beyond 6?

Question 13

the skeletal muscles derived from somites are innervated by ___ nerves & some of the ___ nerves & are said to be innervated by (somatic/visceral) (sensory/motor) fibers (___)

the skeletal muscles derived from branchial arches & innervated by the a branchiomeric cranial nerves are said to be innervated by ___ (sensory/motor) fibers (___)

Answer 13

spinal
cranial
somatic motor fibers (general somatic efferent)

branchial motor fibers (special visceral efferent)

Question 14

oculomotor nerve (III):

cranial nerve

ganglion

target structures (2)

Answer 14

parasympathetic (motor) root of the ciliary ganglion (preganglionic fibers)

ciliary ganglion (postganglionic fibers)

ciliary muscle
sphincter of the pupil

Question 15

facial nerve (VII) (nervus intermedius portion):

cranial nerve (g)

ganglion

target structures (3)

Answer 15

greater petrosal nerve (preganglionic fibers)

pterygopalatine ganglion (postganglionic fibers)

lacrimal gland
nasal glands
palatine glands

Question 16

facial nerve (VII) (nervus intermedius portion):

cranial nerve (c)

ganglion

target structures (3)

Answer 16

chorda tympani nerve (preganglionic fibers)

submandibular ganglion (postganglionic fibers)

submandibular gland
sublingual gland
lingual glands

Question 17

glossopharyngeal nerve (IX):

cranial nerve

ganglion

target structure (1)

Answer 17

lesser petrosal nerve (preganglionic fibers)

otic ganglion (postganglionic fibers)

parotid gland

Question 18

olfactory nerve (CN I):

primitive (sensory/motor) nerve containing specialized (unipolar/bipolar) neurons in the ___ mucosa

bundles of axons from these neurons constitute olfactory nerves which proceed through the ___ plate of the ___ bone & end in the ___ of the (forebrain/midbrain/hindbrain)

contains special (sensory/motor) fibers for ___

Answer 18

sensory
bipolar
olfactory

cribriform plate of the ethmoid bone
olfactory bulb
forebrain

sensory
smell

Question 19

optic nerve (CN II):

travels through the ___ along w/ the ___ artery

contains special (sensory/motor) fibers for ___

Answer 19

optic canal
ophthalmic

sensory
sight

Question 20

oculomotor nerve (CN III):

contains (somatic/visceral) (sensory/motor) & (sympathetic/parasympathetic) fibers

emerges from the ventral aspect of the (forebrain/midbrain/hindbrain) & proceeds through the lateral wall of the ___ sinus & enters the orbit through the ___ fissure where it immediately divides into two divisions (2)

Answer 20

somatic motor
parasympathetic

midbrain
cavernous
superior orbital

superior
inferior

Question 21

oculomotor nerve (CN III):

muscles that the superior division supplies (2)

Answer 21

levator palpebrae superioris

superior rectus eye

Question 22

oculomotor nerve (CN III):

muscles that the inferior division supplies (3)

Answer 22

medial rectus eye
inferior rectus eye
inferior oblique eye

Question 23

oculomotor nerve (CN III):

the only ocular muscles not supplied by the oculomotor nerve (2)

Answer 23

superior oblique (CN IV)
lateral rectus (CN VI)

Question 24

oculomotor nerve (CN III):

the preganglionic parasympathetic fibers of the oculomotor nerve travel w/ the ___ division & depart from it as the (sympathetic/parasympathetic) (sensory/motor) root of the ___ ganglion

these fibers synapse w/ (preganglionic/postganglionic) (sympathetic/parasympathetic) neurons in the ___ ganglion

Answer 24

inferior
parasympathetic
motor
ciliary

postganglionic
parasympathetic
ciliary

Question 25

oculomotor nerve (CN III): postganglionic parasympathetic fibers depart from the ciliary ganglion within the ___ nerves & proceed to the eyeball where they supply: - ___ muscle (involved in accommodation of the lens for near vision) - ___ (which controls the amount of light entering the eye)

Answer 25

short ciliary - ciliary - sphincter of the pupil

Question 26

oculomotor nerve (CN III): the antagonist of the sphincter of the pupil is the ___ which is supplied by (preganglionic/postganglionic) (sympathetic/parasympathetic) fibers arising from the ___ ganglion

Answer 26

dilator of the pupil postganglionic sympathetic superior cervical

Question 27

trochlear nerve (CN IV): emerges from the (dorsal/ventral) aspect of the (forebrain/midbrain/hindbrain) supplies the ___ muscle w/ (somatic/visceral) (sensory/motor) fibers it passes through the lateral wall of the ___ sinus & enters the orbit through the ___ fissure

Answer 27

dorsal midbrain superior oblique eye muscle somatic motor fibers cavernous superior orbital

Question 28

abducens nerve (CN VI): supplies the ___ muscle w/ (somatic/visceral) (sensory/motor) fibers it passes through the ___ sinus in the company of the ___ artery & enters the orbit through the ___ fissure

Answer 28

lateral rectus eye muscle somatic motor fibers cavernous sinus internal carotid artery superior orbital fissure

Question 29

nerve "formula"

Answer 29

SO4 LR6 AR3 superior oblique - CN 4 laterla rectus - CN 6 all the rest - CN 3

Question 30

vestibulocochlear nerve (CN VIII): divisions (2) enters the ___ meatus in the company of the ___ nerve first division conveys (sensory/motor) information related to ___ & ___ second division conveys (sensory/motor) information related to ___

Answer 30

vestibular cochlear internal acoustic meatus facial nerve sensory balance & equilibrium sensory hearing

Question 31

glossopharyngeal nerve (CN IX): mixed ___ & ___ nerve carries (pre/post-ganglionic) (symp/parasymp) fibers nerve to the ___ branchial arch

Answer 31

sensory & motor preganglionic parasympathetic fibers third

Question 32

glossopharyngeal nerve (CN IX): emerges from the ___ from a groove called the ___ sulcus its sensory fibers originate from pseudounipolar neurons in its two sensory ganglia (___ & ___), which are located in the ___ foramen it exits the skull through the ___ foramen along w/ the ___ nerve (CN ___) & the ___ nerve (CN ___)

Answer 32

medulla oblongata post olivary sulcus superior & inferior jugular foramen ``` jugular foramen vagus nerve (CN X) accessory nerve (CN XI) ```

Question 33

``` glossopharyngeal nerve (CN IX): major branches: ``` ``` ___ branch ___ nerve (sensory/motor) branch to the ___ muscle ___ & ___ branches ___ branch ```

Answer 33

``` tympanic branch carotid nerve motor branch to the stylopharyngeus muscle pharyngeal & tonsillar branches lingual branch ```

Question 34

``` glossopharyngeal nerve (CN IX): tympanic branch: ``` enters the ___ cavity contains all of the (pre/post-ganglionic) (symp/parasymp) fibers of the glossopharyneal nerve & (sensory/motor) fibers for the ___ cavity

Answer 34

tympanic cavity preganglionic parasympahtetic fibers sensory fibers for the tympanic cavity

Question 35

``` glossopharyngeal nerve (CN IX): tympanic branch: ``` the tympanic nerve plus (pre/post-ganglionic) (symp/parasymp) fibers from the superior cervical ganglion & a twig from the facial nerve form the ___ plexus within the tympanic cavity the preganglionic parasympathetic fibers within this plexus then converge as the ___ nerve which passes out of the ___ portion of the ___ bone in the hiatus of the ___ nerve side by side w/ the ___ nerve of CN ___

Answer 35

postganglionic sympathetic fibers tympanic plexus ``` lesser petrosal nerve petrous portion temporal bone hiatus of the lesser petrosal nerve greater petrosal nerve of CN VIII ```

Question 36

``` glossopharyngeal nerve (CN IX): tympanic branch: ``` the lesser petrosal nerve then passes out of the skull through the ___ & enters the ___ fossa it synapses in the ___ ganglion w/ (pre/post-ganglionic) (symp/parasymp) neurons these fibers then join the ___ nerve (___) which distributes them to the ___ gland

Answer 36

foramen ovale infratemporal fossa otic ganglion postganglionic parasympathetic neurons ``` auriculotemporal nerve (V3) parotid gland ```

Question 37

``` glossopharyngeal nerve (CN IX): carotid nerve: ``` carries (sensory/motor) fibers from ___ (pressure) in the ___ sinus & ___ in the ___ body

Answer 37

sensory fibers baroreceptors carotid sinus chemoreceptors carotid body

Question 38

``` glossopharyngeal nerve (CN IX): motor branch to the stylopharyngeus muscle: ``` only muscle innervated by the ___ nerve

Answer 38

glossopharyngeal

Question 39

``` glossopharyngeal nerve (CN IX): pharyngeal & tonsillar branches: ``` responsible for general sensation from the mucous membrane of much of the ___ & the ___

Answer 39

pharynx | palatine tonsils

Question 40

``` glossopharyngeal nerve (CN IX): lingual branch: ``` general sensation for the posterior one-third of the ___ ___ fibers for the posterior one-third of the ___

Answer 40

tongue taste fibers tongue

Question 41

lesions of the glossopharyngeal nerve: lesions of the glossopharyngeal nerve don't induce obvious symptoms assuming the ___ nerve is intact for contraction of the ___ muscles however, intactness can be tested through the (afferent/efferent) limb of the ___ reflex (e.g., stroking the posterior one-third of the tongue w/ a spatula) the (afferent/efferent) limb of this reflex is the ___ nerve (CN ___) the glossopharyngeal nerve can be assessed by testing ___ on the posterior one-third of the ___ the pain referred to the middle ear experienced by a person w/ ___ is due to the fact that CN IX supplies the ___ region as well as the mucous membrane of the middle ear

Answer 41

vagus nerve pharyngeal muscles afferent limb gag reflex ``` efferent limb vagus nerve (CN X) ``` taste tongue tosnillitis tonsillar region

Question 42

vagus nerve (CN X): nerve of the ___, ___, & ___ branchial arches mixed ___ & ___ nerve & contains (pre/post-ganglionic) (symp/parasymp) fibers emerges from the ___ form the ___ sulcus

Answer 42

fourth, fifth, & sixth mixed sensory & motor preganglionic parasympathetic medulla oblongata post-olivary sulcus

Question 43

vagus nerve (CN X): leaves the skull through the ___ foramen w/ the ___ & ___ nerves the (sensory/motor) fibers of the vagus nerve originate from pseudounipolar neurons of the ___ & ___ ganglia, which are located in the ___ foramen

Answer 43

jugulra foramen glossopharyneal & accessory nerves sensory superior & inferior ganglia jugular foramen

Question 44

``` vagus nerve (CN X): major branches (8) ```

Answer 44

``` meningeal branch auricular branch pharyngeal branch carotid branch aortic branch recurrent laryngeal nerves vagal branches below the recurrent laryngeal nerves ```

Question 45

vagus nerve (CN X): major branches: meningeal branch: (sensory/motor) to the ___ mater in the posterior ___ fossa actually consists of (sensory/motor) branches from the ___ nerves, which "hitchhike" on the vagus

Answer 45

sensory dura mater posterior cranial fossa sensory upper cervical nerves

Question 46

vagus nerve (CN X): major branches: auricular branch: supplies the ___ meatus & the external surface of the ___ membrane important b/c irritation may initiate a ___ reflex or ___

Answer 46

external auditory meatus tympanic membrane cough reflex nausea

Question 47

vagus nerve (CN X): major branches: pharyngeal branch: main (sensory/motor) nerve to the ___ contains (sensory/motor) fibers this branch, along w/ the pharyngeal branch of cranial nerve IX & postganglionic sympathetic fibers from the superior cervical ganglion, constitute the ___ plexus

Answer 47

sensory pharynx sensory & motor pharyngeal plexus

Question 48

vagus nerve (CN X): major branches: pharyngeal branch: supplies (sensory/motor) fibers to all of the muscles of the ___ except the ___ & all of the muscles of the ___ except the ___ the (sensory/motor) fibers supply part of the mucosa of the ___

Answer 48

pharynx stylopharngeus (CN IX) palate tensor of the palate (V3) pharynx

Question 49

vagus nerve (CN X): major branches: carotid branch: caries (sensory/motor) fibers from ___ (pressure) in the ___ sinus & ___ in the ___ body

Answer 49

sensory baroreceptors carotid sinus chemoreceptors carotid body

Question 50

vagus nerve (CN X): major branches: aortic branch: carries (sensory/motor) fibers from ___ (pressure) in the ___ & ___ in the ___ body (adjacent to the aortic arch)

Answer 50

sensory aortic baroreceptors aortic arch chemoreceptors aortic body

Question 51

vagus nerve (CN X): major branches: superior laryngeal branch: divides into two branches: - sensory: ___ - motor: ___

Answer 51

- internal laryngela branch | - external laryngeal branch

Question 52

vagus nerve (CN X): major branches: superior laryngeal branch: internal laryngeal nerve: pierces the ___ membrane & supplies the lining of the ___ as far as the vocal cords also sends branches to the ___ & the valleculae of the ___ note: the fibers proceeding to the valleculae & to the laryngeal of the epiglottis contain ___ fibers

Answer 52

thyrohyoid membrane larynx epiglottis tongue taste

Question 53

vagus nerve (CN X): major branches: superior laryngeal branch: external laryngeal nerve: supplies the ___ muscle & the ___ portion of the ___ the remaining intrinsic muscles of the larynx are supplied by the ___ nerve

Answer 53

cricothyroid muscle cricopharyngeus portion inferior constrictor recurrent laryngeal nerve

Question 54

vagus nerve (CN X): major branches: recurrent laryngeal nerves: the vagus nerves proceed in the neck within the ___ behind & between the ___ artery & the ___ vein on the left, the vagus nerve passes in front of the ___ the left recurrent laryngeal nerve arches below & behind the ___ to the left of the ___ & ascends in the groove b/n the ___& the ___

Answer 54

carotid sheath internal carotid artery internal jugular vein arch of the aorta aorta ligamentum arteriosum trachea esophagus

Question 55

vagus nerve (CN X): major branches: recurrent laryngeal nerves: the right recurrent laryngeal nerve originates just below the beginning of the ___ artery arching below & behind it to ascend to the ___ in the groove b/n the ___& ___ the recurrent laryngeal nerves supply motor fibers to all of the muscles of the ___ except the ___ muscle & sensory fibers to the ___ & ___ below the level of the vocal cords

Answer 55

subclavian artery larynx trachea & esophagus larynx cricothyroid muscle trachea & larynx

Question 56

vagus nerve (CN X): major branches: vagal branches below the recurrent laryngeal nerves: all vagal branches below the recurrent laryngeal nerves carry (pre/post-ganglionic) (symp/parasymp) fibers & (somatic/visceral) (sensory/motor) fibers for the ___ viscera & ___ organs including the foregut & midgut derivatives

Answer 56

preganglionic parasympathetic fibers visceral sensory fibers thoracic viscera abdominal organs

Question 57

lesions of the vagus nerve: symptoms of a lesion in the vagus nerve may include: - increased ___ - constant ___ - decreased rate of ___ - a sensations of ___ - a ___, ___ voice - difficulty ___

Answer 57

- increased pulse rate - constant nausea - decreased rate of respiratoin - sensation of suffocation - hoarse, low voice - swallowing

Question 58

lesions of the vagus nerve: tests used to confirm a lesion of the vagus nerve include: - the (afferent/efferent) (sensory/motor) limb of the ___ reflex (contraction of the pharyngeal constrictors upon touching the pharyngeal wall or the base of the tongue) - faulty movement of the ___ - a paralyzed ___ on the affected side as seen w/ a laryngoscope

Answer 58

- efferent motor, gag - uvula - vocal cord

Question 59

accessory nerve (CN XI): considered to be the nerve of the ___ branchial arches beyond the ___ emerges from the side of the ___ cervical segments of the spinal cord b/n the ___ & ___ rootlets of the respective spinal nerves

Answer 59

hypothetical sixth upper five dorsal & ventral

Question 60

accessory nerve (CN XI): ascends through the ___ & exits the skull through the ___ foramen along w/ the ___ & ___ nerves innervates the ___ muscle & the ___ muscle

Answer 60

foramen magnum jugular foramen glossopharyngeal & vagus nerves sternocleidomastoid muscle trapezius muscle

Question 61

lesion of the spinal accessory nerve: lesion of this nerve will result in weakness in turning the ___ to the opposite side as well as sagging of the ___

Answer 61

head | shoulder

Question 62

hypoglossal nerve (CN XII): a pure (sensory/motor) nerve emerges from the ___ form the ___ sulcus in line w/ the ___ roots of the spinal nerves

Answer 62

motor medulla oblongata pre-olivary sulcus ventral roots

Question 63

hypoglossal nerve (CN XII): leaves the cranial cavity through the ___ canal supplies all of the ___ & ___ muscles of the ___ w/ the exception of the ___, which is supplied by the vagus nerve

Answer 63

hypoglossal intrinsic & extrinsic muscles of the tongue palatoglossus

Question 64

lesion of the hypoglossal nerve: results in ___ & ___ of the ___ muscles of the tongue the tongue, when protruded, turns to the (same/opposite) side of the lesion due to the unapposed action of the ___ muscle from the (affected/unaffected) side all sensations for touch, pressure, temperature, & taste are (affected/unaffected)

Answer 64

paralysis & atrophy instrinsic muscles same genioglossus muscle unaffected side unaffected

Question 65

movements of the eyeball: the center of the cornea or the center of the pupil is used as the anatomic (anterior/posterior) pole of the eye all movements of the eye are then related to the direction of the movement of the pole as it rotates on any one of the three axes (3)

Answer 65

anterior pole horizontal vertical sagittal

Question 66

eyeball movement terminology: movement of the eye upward: ___ movement of the eye downward: ___ movement of the eye laterally: ___ movement of the eye medially: ___ medial rotation of the upper rim of the cornea (12 o'clock position): ___ lateral rotation of the upper rim of the cornea (12 o'clock position): ___

Answer 66

elevation depression abduction adduction intorsion extorsion

Question 67

basic muscle actions of the eyeball: b/c the ___ & ___ recti are inserted on the medial side of the vertical axis of the eyeball, they not only ___ & ___ the cornea respectively, but also ___ it medially for the (superior/inferior) rectus muscle to raise the cornea directly upward, the (superior/inferior) oblique muscle must assist for the (superior/inferior) rectus muscle to depress the cornea directly downward, the (superior/inferior) oblique muscle must assist

Answer 67

superior & inferior raise & depress rotate superior inferior inferior superior