Term 3 Exam Cranial Nerves

Question 1

How many cranial nerves are there?

Where do they pass through?

Where do they arise?

Answer 1

12 cranial nerves

that pass through various foramina in the bones of the cranium

and arise from the brain

Question 2

Cranial nerves ___, ____, and ____ contain only axons of sensory neurons and are termed the:

Answer 2

Cranial nerves I , II, and VIII contain only axons of sensory neurons and are termed the: special sensory nerves

Question 3

Cranial nerves ___, ____, ___, and ____ contain only axons of motor neurons and are termed the :

Answer 3

Cranial nerves III, IV, VI, and XII contain only axons of motor neurons and are termed the: motor nerves

Question 4

Cranial nerves __,__,___,__, and ___ contain axons of both sensory and motor neurons and are termed:

Answer 4

Cranial nerves V, VII, IX, X, and XI contain axons of both sensory and motor neurons and are termed: mixed nerves

Question 5

Where are the cell bodies of sensory neurons located (with the exception of all proprioceptive sensory neurons)?

Answer 5

In ganglia outside the brain

Question 6

Where are proprioceptive sensory neurons located and where are their cell bodies?

Answer 6

Located in head regions with cell bodies in the mesencephalic ganglion

Question 7

Which two pairs of cranial nerves have their origin in the forebrain?

Answer 7

I and II

Question 8

Which two pairs of cranial nerves originate in the Midbrain (of the brainstem)?

Answer 8

III and IV

Question 9

Which five pairs of cranial nerves have their origin in the Medulla oblongata (of the Brainstem)?

Answer 9

1. VIII
2. IX
3. X
4. XI
5. XI

Question 10

Which three pairs of cranial nerves have their origin in the Pons (of the brainstem)?

Answer 10

1. V
2. VI
3. VII

Question 11

Cranial Nerve I:

• Name:
• Location:
• Sensory/Motor/Mixed?
• Organ it innervates
• Function

Answer 11

Cranial Nerve I:

• Name: Olfactory (I)
• Location: Forebrain
• Sensory/Motor/Mixed: Sensory
• Organ it innervates: Nose
• Function: Olfaction (smell)

Question 12

Cranial Nerve II:

Name:

Location:

Sensory/Motor/Mixed?

Organ it innervates

Function

Answer 12

Cranial Nerve II:

Name: Optic (II)

Location: Forebrain

Sensory/Motor/Mixed: Sensory

Organ it innervates: Eye

Function: Vision (sight)

Question 13

Cranial Nerve III:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Organ it innervates:
• Function(s): (3)

Answer 13

Cranial Nerve III:

• Name: Oculomotor (III)
• Location: Midbrain (of Brainstem)
• Sensory/Motor/Mixed: Motor
• Organ it innervates: All eye muscles except those supplied by IV and VI
• Function:
  
  • Movement of eyeballs and upper eyelids
  • Adjust lens for near vision (accommodation)
  • Constriction of pupils

Question 14

Cranial Nerve IV:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Organ it innervates:
• Function(s): (1)

Answer 14

Cranial Nerve IV:

• Name: Trochlear (IV)
• Location: Midbrain
• Sensory/Motor/Mixed: Motor (somatic)
• Organ it innervates: Superior oblique muscle (of Eye)
• Function(s): Movement of eyeballs

Question 15

Cranial Nerve V:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Organ it innervates:
• Function(s): (2)

Answer 15

Cranial Nerve V:

• Name: Trigeminal (V)
• Location: Pons
• Sensory/Motor/Mixed: Mixed
• Organ(s) it innervates:
  
  • Sensory: Face, sinuses, teeth etc
  • Motor: muscles of mastication
• Function(s):
  
  • Sensory: touch, pain, thermal sensations from the scalp, face, oral cavity
  • Motor (branchial): Chewing and control of middle ear muscle

Question 16

Cranial Nerve VI:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s):

Answer 16

Cranial Nerve VI:

• Name: Abducens (VI)
• Location: Pons
• Sensory/Motor/Mixed: Motor (somatic)
• Innervates: External rectus muscle
• Function: Movement of eyeballs

Question 17

Cranial Nerve VII:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s):

Answer 17

Cranial Nerve VII:

• Name: Facial (VII)
• Location: Pons
• Sensory/Motor/Mixed: Mixed
• Innervates: Muscles of the face
• Function(s):
  
  • Motor:
    
    • Branchial: Control muscles of facial expression and middle ear muscle
    • Autonomic: Secretion of tears and saliva
  • Sensory:
    
    • Taste from anterior 2/3 of tongue
    • touch, pain, and thermal sensations from skin in external ear canal

Question 18

Cranial Nerve VIII:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s):

Answer 18

Cranial Nerve VIII:

• Name: Vestibulocochlear (VIII)
• Location: Medulla oblongata
• Sensory/Motor/Mixed: Special Sensory
• Innervates: Inner ear
• Function(s): Hearing and equilibrium

Question 19

Cranial Nerve IX:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s): (6)

Answer 19

Cranial Nerve IX:

• Name: Glossopharyngeal (IX)
• Location: Medulla Oblongata
• Sensory/Motor/Mixed: Mixed
• Innervates:
  
  • Motor: Pharyngeal musculature
  • Sensory: Posterior part of tongue, tonsil and pharynx
• Function(s): (6)
  
  • Sensory:
    
    • taste from posterior 1/3 of tongue
    • Proprioception in some swallowing muscles
    • Monitoring of blood pressure/oxygen/carbon dioxide levels in blood
    • touch, pain, thermal sensations from skin and external ear and upper pharynx
  • Motor (Branchial): Assist in swallowing
  • Motor (autonomic): Secretion of saliva

Question 20

Cranial Nerve X:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s): (9)

Answer 20

Cranial Nerve X:

• Name: Vagus (X)
• Location: Medulla oblongata
• Sensory/Motor/Mixed: Mixed
• Innervates:
  
  • Motor: heart, lungs, bronchi, GI tract
  • Sensory: Heart, lungs, bronchi, trachea, larynx, pharynx, GI tract, external ear
• Function(s):
  
  • Sensory:
    
    • taste from epiglottis
    • Proprioception from throat and voice box muscles
    • Monitoring of blood pressure/oxygen/carbon dioxide levels in blood
    • touch, pain, thermal sensations from skin of external ear
    • sensations from thoracic and abdominal organs
  • Motor (branchial): Swallowing, vocalization, coughing
  • Motor (autonomic):
    
    • Motility and secretion of gastrointestinal organs
    • Constriction of respiratory passageways
    • Decrease in heart rate

Question 21

Cranial Nerve XI:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s):

Answer 21

Cranial Nerve XI:

• Name: Accessory (XI)
• Location: Medulla Oblongata
• Sensory/Motor/Mixed: Mixed
• Innervates: Sternocleidomastoid and trapezius muscles
• Function(s):
  
  • Sensory: proprioception and pain from trapezius and sternocleidomastoid muscles
  • Motor: Movement of head and pectoral girdle

Question 22

Cranial Nerve XII:

• Name:
• Location:
• Sensory/Motor/Mixed:
• Innervates:
• Function(s):

Answer 22

Cranial Nerve XII:

• Name: Hypoglossal (XII)
• Location: Medulla oblongata
• Sensory/Motor/Mixed: Motor
• Innervates: Muscles of the tongue
• Function(s): Motor (somatic): speech, manipulation of food and swallowing

Question 23

The olfactory nerves end in the brain in paired masses of grey matter called the ________ that rest on the ______

Answer 23

The olfactory nerves end in the brain in paired masses of grey matter called the Olfactory bulbs that rest on the cribriform plate

Question 24

Within the olfactory bulbs, the axon terminals of olfactory receptors form synapses with dendrites and the axons of these neurons make up the _______ which extend posteriorly from the olfactory bulbs

Answer 24

Within the olfactory bulbs, the axon terminals of olfactory receptors form synapses with dendrites and the axons of these neurons make up the olfactory tracts which extend posteriorly from the olfactory bulbs

Question 25

The two optic nerves merge to form the ______

Answer 25

optic chiasm

Question 26

What happens within the optic chiasm

Answer 26

• axons from the medial half of each eye cross to the opposite side while axons from the lateral half remain on the same side

Question 27

Posterior to the optic chiasm, the regrouped axons form the ____

Answer 27

optic tracts

Question 28

Most axons in the optic tracts end in the _____ nucleus of the thalamus

Answer 28

Most axons in the optic tracts end in the lateral geniculate nucleus of the thalamus

Question 29

The trigeminal (V) nerve is the largest of the cranial nerves and has three branches:

Answer 29

1. Ophthalmic nerve
2. Maxillary nerve
3. Mandibular nerve

Question 30

What are the two branches of the Vestibulocochlear (VIII) nerve?

Answer 30

1. Vesticular branch - equilibrium
2. Cochlear branch - hearing

Question 31

Motor axons of the glossopharyngeal (IX) nerve arise in the nuclei of the _____ and exit the skull through the ______

Answer 31

Motor axons of the glossopharyngeal (IX) nerve arise in the nuclei of the medulla and exit the skull through the jugular foramen

Question 32

Axons of autonomic motor neurons (parasympathetic) in the vagus nerve originate in nuclei of the _____ and end in the _____ and _____

Answer 32

Axons of autonomic motor neurons (parasympathetic) in the vagus nerve originate in nuclei of the medulla and end in the lungs and heart

Question 33

Vagal parasympathetic axons also supply glands of the _____ and smooth muscle of the ______, _____, _____, ______, _____ and most of the _______

Answer 33

Vagal parasympathetic axons also supply glands of the GI tract and smooth muscle of the respiratory passageway, esophagus, stomach, gallbladder, small intestine, and most of the large intestine