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Caring for Your Eyes and Ears
In this lesson, you will Learn About…
 Keeping your eyes healthy.
 Why people wear glasses or contact lenses.
 Caring for your ears.
Standards
 1: The student will comprehend concepts related to
health promotion to enhance health.
Indictors
 P-8.1.2 Discuss how heredity, lifestyle, behaviors,
environment, and medical care influence an
individual’s health.
Relevance
Caring for Your Eyes and Ears
The Vocabulary terms for this lesson are:
 Optometrist.
 Ophthalmologist.
 Astigmatism.
 Decibel.
Your Eyes
Your eyes tell you about the world—about
light, colors, shapes, and movements.
The data that your eyes gather is
interpreted by your brain, for example, to
help you recognize a friend or the words
on a page.
Structure of the Eye
The optic
nerve is a
bundle of
nerve fibers
that sends
messages to
the brain,
which
interprets
them.
The sclera is the white of
the eye. It covers and
protects the whole eye,
except for the front.
The cornea is the clear
section that lets in light at the
front of the eye.
The iris is the colored part
of the eye. It controls the
size of the pupil.
The pupil is the dark
opening in the center of the
iris. It grows larger in dim
light and smaller in bright
light, so that the right
amount of light enters the
eye.
The retina is the light-sensing
part of the inner eye.
The lens focuses the light on
the retina.
Eye Care
Your sense of sight is important, so you
need to take care of your eyes.




Make sure you have enough light.
Avoid light that is too bright.
Avoid rubbing your eyes.
Protect your eyes from injury.
Eye Examinations
To make sure that your eyes are healthy,
visit an eye care professional for regular
examinations. Eye care professionals
include an optometrist and an
ophthalmologist.
If you wear glasses or contact lenses, have
your eyes checked once a year. Otherwise,
have them checked every two years.
Eye Examinations (cont’d.)
Some of the most common vision problems
include the following:
 Nearsightedness – A vision problem in which a
person can clearly see only objects close to his
or her eyes.
 Farsightedness – A condition in which a person
can see only distant objects clearly.
 Astigmatism – An eye condition in which
images are distorted, causing objects to appear
wavy or blurry.
Vision Correction
Many vision problems can be corrected
with either eyeglasses or contact lenses.
Contacts are available in several basic
types:
 Hard lenses – Made of slightly flexible plastic.
 Soft lenses – Made of soft, flexible plastic.
 Disposable lenses – Can be either hard or soft;
worn for a set period of time and then
replaced with a new pair.
Your Ears
A
The outer ear
is shaped like
a cup to pick
up sound
waves, which
travel through
the external
auditory canal.
B
In the middle ear,
sound waves make
the eardrum vibrate.
The vibrations move
the hammer, the anvil,
and the stirrup. These
bones carry the
vibrations to the inner
ear.
C
In the inner ear, the fluid in the
cochlea moves. Tiny hair cells
lining the cochlea vibrate in
response, sending electronic
messages to the auditory
nerve. These messages travel
to the brain, which identifies
the sound.
Ear Care
Protect your ears from loud sounds.
Sounds over 125 decibels are loud
enough to be painful. Exposure to loud
noises can cause loss of hearing or
tinnitus.
Prolonged exposure to lower levels of
sounds can also harm the ears.
Ear Care (cont’d.)
To protect your ears from noise and to
prevent other problems:
 Keep the volume fairly low on your radio, CD
player, cassette player, and television.
 Wear earplugs and other hearing protection
devices when exposed to loud and prolonged
noises.
 Have periodic hearing tests administered.
Hearing tests can be administered by the
school nurse, speech therapist, or an
audiologist.
Ear Care (cont’d.)
It is important to clean and protect your
ears.
 Clean the outside of your ears with a wet
washcloth.
 On cold days, wear earmuffs or a hat that
covers your ears. Cold air can irritate the
middle ear and cause frostbite on the outer
ear.
 If you think you have an ear infection, are
experiencing pain in one or both ears, or have
trouble hearing, tell your parents or guardians
right away.
Reviewing Terms and Facts
1. Define astigmatism.
Astigmatism is an eye condition in which
images are distorted, causing objects to
appear wavy or blurry.
Reviewing Terms and Facts
2. What is a decibel?
A decibel is the unit for measuring the
loudness of sound.
Thinking Critically
3. What activities or situations in your
life could be harmful to your hearing?
What can you do to protect your
hearing?
Vocabulary Review
An optometrist is a health care
professional who is trained to examine the
eyes for vision problems and to prescribe
corrective lenses.
Vocabulary Review
An ophthalmologist is a physician who
specializes in the structure, functions, and
diseases of the eye.
Vocabulary Review
Astigmatism is an eye condition in which
images are distorted, causing objects to
appear wavy or blurry.
Vocabulary Review
A decibel is the unit for measuring the
loudness of sound.