Week 8 Cranial nerves

Question 1

How many cranial nerves are there?

Answer 1

12 pairs

Question 2

How are the cranial nerves named?

Answer 2

By roman numerals in reference to their attachment to the brain in an anterior to posterior direction
They are named as cranial nerves as they emerge through the foramina or fissures in the cranium/ skull

Question 3

What are the cranial nerves covered in?

Answer 3

Sheaths formed by the cranial meninges

Question 4

Where do most of the cranial nerves arise?

Answer 4

Mainly off the brain stem

Question 5

What portion of the brain stem do the cranial nerves arise?

Answer 5

The medulla, pons and midbrain

Question 6

What is the brain stem?

Answer 6

The connecting link between the remainder of the brain and the spinal cord

Question 7

What are the main functional components of cranial nerves?

Answer 7

motor:
Somatic motor (efferent)
Visceral motor (efferent)
Sensory:
General sensory (touch, pain and temperature)
Visceral sensory (afferent)
Special sensory

Question 8

What do the cranial nerves innervate?

Answer 8

Structures in the head and neck and visceral organs of the trunk

Question 9

What kind of nerve is the olfactory nerve and where does it originate and end?

Answer 9

Cranial nerve 1
Special sensory
Begins at the mucosa of the nasal cavity and ends at the olfactory bulb in the cerebral cortex

Question 10

What is the olfactory nerve composed of and what do they respond to?

Answer 10

Both neurons and receptors

Respond to volatile chemicals

Question 11

Where does the olfactory nerve run?

Answer 11

Through the foramina of the cribirform plate
pierce dura and arachnoid mata
enter olfactory bulb
then becomes the olfactory tract

Question 12

What is the function of the olfactory nerve?

Answer 12

Sense of smell
Arousal of emotions
induce visceral responses through ANS

Question 13

What kind of nerve is the optic nerve?

Answer 13

Cranial nerve 2

Special sensory

Question 14

What is the optic nerves claim to fame?

Answer 14

The largest (thickest) cranial nerve

Question 15

Where is visual information relayed to?

Answer 15

visual coriticies of the occipital lobes

Question 16

What nerve fibres does the occulomotor nerve recieve?

Answer 16

Both parasympathetic and sympathetic fibres.

Question 17

Where does the occulomotor nerve begin and end?

Answer 17

Cranial nerve 3
originates in the midbrain
it then leaves the cranial cavity
then enters the orbit through the superior orbital fissure

Question 18

What are the functions of the occulomotor nerve?

Answer 18

Provides motor function to 4 extraocular muscles
motor supply to the upper eyelid
Supplies parasympathetics to the sphincter of the pupil and cillary muscle of the lens

Question 19

Where does the trochlea nerve originate?

Answer 19

Cranial nerve 4

The midbrain, it emerges from its dorsally from the brainstem

Question 20

What is the trochlea nerves claim to fame?

Answer 20

Longest intracranial course

Question 21

What is the function of the trochlea nerve?

Answer 21

somatic motor nerve to one of the extraocular muscles and proprioception

Question 22

Where does the trigeminal nerve originate from?

Answer 22

Cranial nerve 5

Originates from the pons and is the second largest cranila nerve

Question 23

What fibres supply the trigeminal nerve?

Answer 23

Somatic motor fibres and somatic sensory fibres

Question 24

How many components of the trigeminal nerve are there?

Answer 24

3:
opthalmic
maxillary
Mandibular

Question 25

What does the trigeminal nerve supply through sensory innervation?

Answer 25

``` Face Teeth Mouth Nasal cavity Dura ```

Question 26

Where does the abducens nerve emerge?

Answer 26

From the brain stem between the pons and the medulla

Question 27

What is the function of the abducens nerve?

Answer 27

somativ motor nerve to an extraocular muscle and proprioception. Also abducts the eye

Question 28

Where does the facial nerve arise?

Answer 28

from the junction of the pons and medulla

Question 29

What is the facial nerves pathway?

Answer 29

passes through internal acoustic miatus through the facial canal within the temporal bone exits through the stylomastoid foramen It then enters the parotid galnd where it gives off terminal branches

Question 30

What is the facial nerves claim to fame?

Answer 30

It is the longest interossues Cranial nerve

Question 31

What nerve fibres does the facial nerve have?

Answer 31

Special sensory fibres Somatic sensory fibres Somatic motor fibres Visceral motor fibres

Question 32

What are the roots of the facial nerve and how many are there?

Answer 32

2 roots Larger motor root: supplies muscles of facial expression Smaller intermediate root: Carries taste, somatic sensory fibres and parasympathetics

Question 33

What are the unctions of the facial nerve?

Answer 33

taste to the anterior 2/3rds of the tongue and softa palate sensory to the external ear motor to the muscles of facial expression, throat and middle ear Proprioception to the above muscles parasympathetic supply to submandibular and sublingual salivary glands icramal gland, glands of the nasal cavity and palate

Question 34

What are the terminal branches of the facial nerve?

Answer 34

``` Posterior auricular Temporal Zygomatic Buccal Mandibular Cervical ```

Question 35

Where does the Vestibulocochlea nerve arise?

Answer 35

Cranial nerve 8 | between the pons and the medualla

Question 36

What is the vestibulocochlea nerves claim to fame?

Answer 36

It is the only cranial nerve that does nt exit the skull

Question 37

What are the functions of the vestibulochochlea nerve?

Answer 37

Special sensory supply state of balance hearing

Question 38

Where does the glossopharyngeal nerve begin?

Answer 38

Cranial nerve 9 | From the medulla

Question 39

Where does the glossophrangeal nerve exit?

Answer 39

Through the jugular foramen

Question 40

What are the functions of the glossophrangeal nerve?

Answer 40

``` Special sensory supply Taste Somatic sensory Visceral sensory somatic motor visceral motor Proprioception ```

Question 41

What kind of nerve fibres does the glossopharangela nerve have?

Answer 41

Parasympathetic

Question 42

What does vagus mean?

Answer 42

Cranial nerve 10 | Wandering

Question 43

What is the vagus nerves claim to fame

Answer 43

it is the longest cranial nerve

Question 44

Where does the vagus nerve originate and leave the skull?

Answer 44

roots from the medulla | leaves the skull through the jugular foramen

Question 45

What are the functions of the vagus nerve?

Answer 45

``` sensory to: Inferior pharynx Larynx Thoracic and abdominal organs special sensory ```

Question 46

What does the vagus nerve have somatic motor supply to?

Answer 46

``` Soft palate Pharynx Intrinsic laryngeal muscle palaglotus muscle proprioception ```

Question 47

What do the parasympathetic fibres of the vagus nerve supply?

Answer 47

Thoracic and abdominal viscera

Question 48

How many roots does the spinal accessory nerve have?

Answer 48

2; Cranial root Spinal root

Question 49

Where does the cranial root originate from on the spinal accessory nerve?

Answer 49

from the medulla

Question 50

Where does the Spinal root originate from on the spinal accessory nerve?

Answer 50

upp 5-6 cervical segments, via passing through the foramen magnu,

Question 51

What are the functions of the spinal accessory nerve?

Answer 51

``` motor supply to: soft palate pharynx SCM Trapezius ```

Question 52

Where does the hypoglossal nerve arise from and where does it exit the cranium?

Answer 52

CN 12 The Medulla exits through the hypoglossal canal

Question 53

What are the functions of the hypoglossal nerve?

Answer 53

motor nerve to the muscles of the tongue | proprioceptive fibres for these muscles