Chapter 10 (Summary of Cranial Nerves)

Question 1

(Cranial Nerves)

Cranial nerves are bundles of sensory or motor fibers that:

Answer 1

• Innervate muscles/glands

- Carry impulses from sensory receptors, or have a combination of motor and sensory fibers

Question 2

(Cranial Nerves)
There are ____ ____ of cranial nerves in the PNS that will merge from the cranial cavity via _____ or _____ in the cranium.

Answer 2

12 pairs; foramina or fissures

Question 3

(Cranial Nerves)

All nerves except one (______) will originate from the brain.

Answer 3

CN XI

Question 4

(Cranial Nerves)

The cranial nerves will carry one or more of the following main functional components:

Answer 4

• Motor (efferent) fibers

- Sensory (afferent) fibers

Question 5

(Cranial Nerves)

Motor fibers

Answer 5

• to voluntary (striated) muscle

- to involuntary (smooth) muscles or glands

Question 6

(Cranial Nerves)

Sensory fibers

Answer 6

• Transmitting general sensation from the skin and mucous membranes
• Conveying sensation from the viscera
• Transmitting unique/special sensation

Question 7

(Olfactory Nerve - CN I)

Function:

Answer 7

Special sensory for the sense of smell/olfaction (sensation of odors that result from the detection of odorous substances aerosolized in the environment)

Question 8

(Olfactory Nerve - CN I)

Component:

Answer 8

Special sensory for olfaction

Question 9

(Olfactory Nerve - CN I)

Origin:

Answer 9

Forebrain (cerebral hemispheres)

Question 10

(Olfactory Nerve - CN I)

Cranial Exit:

Answer 10

Foramina in the cribriform plate of ethmoid bone

Question 11

(Optic Nerve - CN II)

Function:

Answer 11

Special sensory for the sense of vision

Question 12

(Optic Nerve - CN II)

Component:

Answer 12

Special sensory for vision

Question 13

(Optic Nerve - CN II)

Origin:

Answer 13

Forebrain (diencephalon)

Question 14

(Optic Nerve - CN II)

Cranial Exit:

Answer 14

Optic canal

Question 15

(Oculomotor Nerve - CN III)

Functions:

Answer 15

• Motor innervation to the striated muscle of 4/6 extra-ocular muscles (superior, medial and inferior recti, inferior oblique) and superior eyelid
• Parasympathetic innervation that causes constriction of the pupil and ciliary muscle to produce accommodation of the eye for near vision

Question 16

(Oculomotor Nerve - CN III)

Component:

Answer 16

Somatic motor and visceral motor

Question 17

(Oculomotor Nerve - CN III)

Origin:

Answer 17

Midbrain (mesencephalon)

Question 18

(Oculomotor Nerve - CN III)

Cranial Exit:

Answer 18

Superior orbital fissure

Question 19

(Trigeminal Nerve - CN V)

Divisions:

Answer 19

• Ophthalmic (CN V1)
• Maxillary (CN V2)
• Mandibular (CN V3)

Question 20

(Trigeminal Nerve - CN V)

Function - CN V1

Answer 20

Somatic sensation to the front of the head and nose

Question 21

(Trigeminal Nerve - CN V)

Function - CN V2

Answer 21

Somatic sensation to the upper jaw (maxilla)

Question 22

(Trigeminal Nerve - CN V)

Function - CN V3

Answer 22

Somatic motor distribution to the muscles of mastication

Question 23

(Trigeminal Nerve - CN V)

Component:

Answer 23

Somatic sensory (CN V1 and V2) Somatic motor (CN V3)

Question 24

(Trigeminal Nerve - CN V)

Origin:

Answer 24

Brainstem (pons)

Question 25

(Trigeminal Nerve - CN V)

Cranial Exit:

Answer 25

Superior orbital fissure - Ophthalmic (CN V1)
Foramen rotundum - maxilla (CN V2)
Foramen ovale - mandible (CN V3)

Question 26

(Abducent Nerve - CN VI)

Function:

Answer 26

Motor function to one extra-ocular muscle, the lateral rectus

Question 27

(Abducent Nerve - CN VI)

Component:

Answer 27

Somatic motor

Question 28

(Abducent Nerve - CN VI)

Origin:

Answer 28

Brainstem (junction between pons and medulla)

Question 29

(Abducent Nerve - CN VI)

Cranial Exit:

Answer 29

Superior orbital fissure

Question 30

(Facial Nerve - CN VII)

Function:

Answer 30

• Special sensory for taste of anterior 2/3 of palate
• Somatic motor to muscles of facial expression and scalp
• General sensation to skin of auricle (ear)
• Parasympathetic innervation to salivary glands, lacrimal gland, and glands of nose and palate

Question 31

(Facial Nerve - CN VII)

Component:

Answer 31

Somatic motor, special sensory (taste), somatic sensory, visceral motor

Question 32

(Facial Nerve - CN VII)

Origin:

Answer 32

Brainstem (junction between pons and medulla)

Question 33

(Facial Nerve - CN VII)

Cranial exit:

Answer 33

Internal acustic meatus, facial canal, stylomastoid foramen