The Ears

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Pg 50 of IAN
The Ears
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Objective
To learn the parts of the ear and how the ear
works.
Research
The visible part of the ear. It is
Outer ear
made of cartilage. It catches sound vibrations.
It is a cavity on the inner side
Middle ear
of the ear drum and protects the inner ear.
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A tightly stretched membrane.
Eardrum
Sound waves cause it to vibrate. Sound is
passed on to three tiny bones.
3 bones involved.
All three bones transfer vibrations through the
middle ear. They magnify gentle sounds and
soften loud sounds.
hammer
1.
anvil
2.
stirrup
3.
Connects the back of the
Eustachian tube
throat to the middle ear and helps keep air
pressure the same on the inside and outside of
the ear.
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Inner ear
Contains the actual organ of hearing.
Give body a sense
1. Semicircular canals
of balance.
Change sound waves to nerve
2. Cochlea
impulses. Spiral shaped, like a snail, and sends
signals to the brain.
Sound waves earflap down canal
Hearing
hammer
anvil
stirrup
eardrum
auditory nerve picks up signals
cochlea
and sends them to the brain where they are
perceived as sound.
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HOW THE EAR WORKS
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semicircular canals
anvil
ear flap
hammer
ear drum
stirrup
cochlea
ear canal
auditory nerve
eustachian tube