Download Facts about CN I

The Cranial Nerves
12th Grade Science
Edgar Garcia
Click to continue
Click on
the
arrow
next to a
cranial
nerve to
learn
more
about it:
Review Question
Olfactory Nerve (CN I)
Facts about CN I:
 Responsible for the sense
of smell
 Receptors located within
the mucosa of nasal cavity
 Shortest cranial nerve
 Sensory fibers extend
through the ethmoid bone
Return to Main
Menu
Optic Nerve (CN II)
Facts about CN II:
 Located behind the eye
 Transfers visual
information to the brain
 Made ganglionic cells
 Contains over one
million nerve fibers
Return to Main
Menu
Oculomotor Nerve (CN III)
Facts about CN III:
 Responsible for eyeball and eyelid movement
 Has two separate components to its structure
 Somatic motor component: allows us to follow an abject as
it moves.
 Visceral motor component: allows us to keep an object in
focus as distance changes
Return to Main
Menu
Trochlear Nerve (CN IV)
Facts about CN IV:
 Only nerve that emerges
near the back of the brain
 Nerve with the longest
pathway
 Helps move the eye up
and down, as well as
outwards
 Smallest nerve that sends
signals from the eye
Return to Main
Menu
Trigeminal Nerve (CN V)
Facts about CN V:
 Transmits sensations from
the face to the brain
 Contains three branches
seen on the graphic
 Transmits sensations to the
mouth, teeth, face, and
nasal cavity
 Also controls muscles used
for chewing
Return to Main
Menu
Abducens Nerve (CN VI)
Facts of CN VI:
 Helps moves the eye
laterally, away from the
nose
 It begins from the
brainstem
 Controls the lateral
rectus muscle
 If nerve is injured, double
vision can occur
Return to Main
Menu
Facial Nerve (CN VII)
Facts about CN VII:
 Sends sensory information
from the tongue and inside
of the mouth
 Helps produce facial
expressions
 Contains three different
branches
 Relays taste sensations
from the tip of the tongue
Return to Main
Menu
Vestibulocochlear Nerve (CN VIII)
Facts about CN VIII:
 There is one in each ear
 Located in the internal
auditory canal
 Responsible for hearing
and balance
 Damage to nerve can
result in vertigo
Return to Main
Menu
Glossopharyngeal Nerve (CN IX)
Facts about CN IX:
 Ends in seven different
branches
 Helps in swallowing
 Part of the pharyngeal
plexus with the vagus nerve
 Receives information from
the tongue, tonsils,
pharynx, and middle ear
Return to Main
Menu
Vagus Nerve (CN X)
Facts about CN X:
 Longest cranial nerve,
extending to many organs
 Keeps heart rate constant
and controls food digestion
 Part of the involuntary
nervous system
 Stimulation of nerve is
used to treat people with
depression
Return to Main
Menu
Accessory Nerve (CN XI)
Facts about CN XI:
 Controls movement of
some neck muscles
 Contains a spinal and
cranial division
 Controls movement of the
sternocleidomastoid
muscle
 Accessory nerve palsy can
occur if damaged
Return to Main
Menu
Hypoglossal Nerve (CN XII)
Facts about CN XII:
 Controls movements of the
tongue
 Ends on the underside of the
tongue
 Damage to the nerve can result
in tongue paralysis
 Other effects of damage
include: difficulty speaking,
chewing, and/or swallowing
Return to Main
Menu
Review Question
Which of the following is the
longest of the twelve cranial
nerves?
A. Vestibulocochlear Nerve
B. Vagus Nerve
C. Olfactory Nerve
There are other nerves longer
than the vestibulocochlear nerve!
Go back and try again!
Return to Question
There are other nerves longer than the
olfactory nerve!
Go back and try again!
Return to Question
Great Work!
The vagus nerve is the longest of the
cranial nerves, it connects to multiple
organs!
Click to continue
Congratulations! You have
completed this lesson on the twelve
cranial nerves!
Click on the brain below to return to
the title slide for the next student to
learn: