3.04 Functions and
disorders of the ear
3.04 Understand the functions and
disorders of the sensory system
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3.04 Understand the functions and
disorders of the sensory system
Essential Questions
•What are the functions of the sensory system?
•What are some disorders of the sensory system?
•How are sensory system disorders treated?
•How do you relate the body’s communication to
the sensory system?
3.04 Understand the functions and
disorders of the sensory system
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Understanding the
functions of the ear:
Hearing
3.04 Understand the functions and
disorders of the sensory system
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Understanding the functions of the ear
External ear
Pinna-collects
sound
waves
External auditory canal

Contains cerumen-ear
wax that protects the ear
Tympanic
membranetransmits soundwaves to
the ossicles
https://www.youtube.co
m/watch?v=Slcg7cbAG
Zs
3.04 Understand the functions and
disorders of the sensory system
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Understanding the functions of the ear
*Middle ear
*Ossicles-3
tiny bones
malleus, incus and
stapes that transmit
sound waves from the
ear drum to the inner
ear.
Eustachian
tubeequalizes air pressure
in the middle ear.
3.04 Understand the functions and
disorders of the sensory system
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Understanding the functions of the ear
Inner ear
Cochlea-contains
the
organ of Corti that
transmits vibrations to
the hearing center of
the brain.
Semicircular
canalscontain a liquid that
sends messages to
cerebellum to maintain
balance/equilibrium.
3.04 Understand the functions and
disorders of the sensory system
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Understanding the functions of the ear
Pathway of hearing
Sound
waves---pinna--auditory canal---typmanic
membrane---ossicles--stimulate cochlea---cochlea
nerve---temporal lobe for
interpretation
What
are decibels?
The measurement of sound
https://www.youtube.com/w
atch?v=uCnsw9oRDsM
3.04 Understand the functions and
disorders of the sensory system
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Understanding
the
functions of
the ear
What is occurring at
each structure?
3.04 Understand the functions and
disorders of the sensory system
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Healthy Hearing
How do you protect your hearing?
What is the relevance to healthy hearing?
3.04 Understand the functions and
disorders of the sensory system
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Understanding the
functions of the ear
Sound Activity
What is a sound byte?
Short bit of sound or clip from a
longer recording.
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
Otoscope-lighted instrument to view the ear
Otolaryngologist-specialist of the ear and throat
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
External otitis-inflammation of the ear canal
Discuss what you see in this
picture? (Besides a Q-tip!)
What causes external otitis?
Bacterial infection due to
excessive water exposure, use of
q-tips
How can it be prevented?
Proper ear care, avoid water
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
*Otitis media-infection of the
middle ear
Who
is most at risk of having
otitis media?
*Most common in children due to a
short eustachian tube; often a
complication of the common cold
*Symptoms: earache, pain, fever,
drainage of fluid from the ear
What
are the treatment options?
Antibiotics, myringotomy (an opening
put in the tympanic membrane), tubes
in the ear
https://www.youtube.com/
watch?v=Nwoi7z2bMmY
Disorders of the ear
Otosclerosis-inherited
disorder; the stapes bone
becomes spongy then
hardens
What
is it?
 Oto- sclerosis
Why
is a stapedectomy useful
in treating otosclerosis?
Hearing is re-routed
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
Meniere’s disease-the semicircular
canals of the inner ear are affected
and vertigo (dizziness) occurs
What
are the symptoms of Meniere’s
disease? Vertigo, nausea, vomiting,
tinnitus (ringing in the ears)
What causes these symptoms?
How is it treated? Bedrest,
medication, avoid salt, caffeine,
nicotine, eat a balanced diet, plenty of
H2O
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Disorders of the ear
*Tinnitus-ringing in the ears
What is tinnitus?
Explain this statement:
Tinnitus is a symptom, not a
disorder.
*May be caused by impacted
wax, otitis media,
otosclerosis, blockage of
blood supply to the cochlea,
loud noises
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
Presbycusis
What
is
presbycusis?
Deafness due to aging
Who
is most likely
to develop
presbycusis?
3.04 Understand the functions and
disorders of the sensory system
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Disorders of the ear
*Conductive hearing
loss is due to wax or
fluid build up that
blocks sound to the
inner ear.
Sensory hearing loss
is caused by damage
to parts of the inner
ear or auditory nerve.
3.04 Understand the functions and
disorders of the sensory system
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Testing for hearing loss
Rinne test
Weber test
Compare these two tests.
How are they diagnostic?
https://www.youtube.com/watch?v=RVH4K4EcsiA
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3.04 Understand the functions and
disorders of the sensory system
Essential Questions
•What are the functions of the sensory system?
•What are some disorders of the sensory system?
•How are sensory system disorders treated?
•How do you relate the body’s communication to
the sensory system?
3.04 Understand the functions and
disorders of the sensory system
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3.04 Functions and
disorders of the ear
The End
3.04 Understand the functions and
disorders of the sensory system
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