Cranial Nerves

Question 1

Olfactory (I)

Answer 1

• Sensory Nerve
• Smell
• olfactory cells converge to become nerve
• begin in superior nasal cavity w/in olfactory epithelium and goes through cribriform plate to synapse on olfactory bulb

Question 2

Optic (II)

Answer 2

• sensory
• axons of ganglion cells in retina of each eye join to form optic nerve
• vision

Question 3

oculomotor (III)

Answer 3

motor

• originates in midbrain
• raise eyelid, move eye up, down, and inward
• superior rectus, medial rectus, inferior rectus, and inferior oblique

Question 4

Trochlear (IV)

Answer 4

• motor
• smallest cranial nerve
• originates in midbrain
• controls lateral and inferior eye movement
• superior oblique

Question 5

Trigeminal (V)

Answer 5

Mixed

• biggest cranial nerve
• 3 branches: ophthalamic, maxillary, and mandibular
• sensation of touch, pain, and temp
• motor axons supply muscles of mastication

Question 6

Abducens (VI)

Answer 6

motor

• originates from pons
• lateral ratation of eye
• lateral rectus

Question 7

Facial (VII)

Answer 7

Mixed

• Sensory: anterior 2/3 of tongue
• motor: facial expressions

Question 8

Vestibulocochlear (VIII)

Answer 8

• sensory
• originates in inner ear
• vestibular branch from vestibular aparatus carries impulses for equilibrium
• cochlear branch carries impulses for hearing from cochlea

Question 9

Glossopharyngeal (IX)

Answer 9

Mixed

• sensory: posterior 1/3 of tongue
• motor: arises from medula and deals with release of saliva

Question 10

Vagus (X)

Answer 10

• mixed
• heart, major arteries, larynx, lungs, abdomen, digestive tract
• 80% of parasympathetic outflow
• distributed fro mhead and neck into thorax and abdomen
• Sensory: tast in throat, and proprioception/stretching
• motor: arise from medulla and supply muscles of pharynx, larynx, soft palate that’re involved with speach and swallowing

Question 11

Acessory (XI)

Answer 11

• motor
• divided into cranial accessory and spinal accessory
• sternocleidomastoid and trapezius to coordinate head, neck, and scapula

Question 12

Hypoglossal (XII)

Answer 12

motor

-conduct nerve impulses for speach and swallowing to innervate tongue