Ch' 7: Personal Health E'Q': Why is it so important to take care of our personal hygiene

1
Ch. 7 Personal HealthE.Q. Why is it so
important to take care of our personal hygiene?

• Lesson 3 Healthy Eyes
• Bell Work Why do people wear glasses?
• List as many reason as you can!

2
Lesson ObjectivesStudents will be able to

• Label the parts of the eye.
• Explain the process of seeing.
• Discuss eye care.
• Describe common vision problems.

3
Health Term to Know

• Lacrimal gland
• Sclera
• Cornea
• Choroids
• Retina

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Your Eyes

• 80 of all info comes from your eyes
• Eyes can see 8 million differences in color
• Surrounded by protective structures
• Eyebrows
• Eyelids
• Eyelashes
• Lacrimal, or the gland
• responsible for producing tears.
• Made of water and salt
• Salt gives it an antiseptic quality to help fight
  pathogens
• Extra tears go into the nasal cavity or spill
  over!

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Parts of the Eye

• Sclera is the tough white outer coating of the
  eye
• Rounded part of the sclera is the cornea.
• Watery fluid behind cornea is the aqueous humor.
• Choroid is the middle layer of the eyeball.
• Retina is the light-sensitive membrane on which
  images are cast by the cornea and lens.
• Millions of receptors called rods and cones
• The eyeball is filled with a clear jelly called
  vitreous humor keeping the eyeball firm.

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Vision

• Starts in the retina
• Light rays pass through the cornea
• They are bent and directed through the pupil
• Pass through the lens which adjusts to focus
  light on retina
• Lens bulges when things are near and flattens
  when things are distant
• Retina changes the visual information into nerve
  impulses which are sent to brain
• Normal vision is called 20/20
• Can read eye chart at 20 feet
• 20/200 is legally blind

7
Healthy Eyes

• Regular check ups
• If corrective lenses are prescribed take breaks
  from using your eye
• Especially when using computer
• Use well-lighted room to watch TV
• Avoid rubbing eyes
• Wear sunglasses
• Wear protective goggles when in engaging in an
  activity or sport

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Eye Problems Vision Problems

• Nearsightedness, or myopia
• Condition where light rays are focused in front
  of the retina rather than on it.
• Farsightedness, or hyperopic
• Occurs when the light rays are focused behind the
  retina
• Astigmatism is the curvature of the lens is
  uneven
• Strabismus is a condition where the muscles of
  both eyes do not work together
• Eyes appear crossed
• Amblyopia is a condition that occurs if
  strabismus goes untreated where reduced vision
  occurs

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Eye Problems Diseases of the Eye

• Sty - inflamed swelling of a sebaceous gland
• Pinkeye or conjunctivitis - eye infection of the
  sclera causing redness and discomfort
• Cataracts clouding of the lens which causes
  blurring or hazy vision
• Glaucoma condition in which pressure of the
  fluid in the eye is too high and damages the
  optic nerve results in blindness
• Detached Retina retina becomes separated from
  the outer layer of the eye as a result of
  degeneration or from injury

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Laser Eye Surgery

• Surgical correction of vision problems
• LASIK a procedure where a flap in the cornea is
  created and the lens is either shaved off or
  added to depending on the problem.
• Guided by a programmed computer
• Risks
• Light sensitivity or scarring of the cornea

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Quiz Time!

• You have 5 minutes!
• You may use your notes!
• You may only use pen NOT pencil or RED pen!
• When you are finished sit quietly and wait for
  others to finish!

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TIME IS UP!

• Take out RED pen.
• I will read the correct responses aloud.
• Mark the ones incorrect with an X over the
  correct answer!
• When we are finished write the correct amount out
  of 10 in box at bottom of page
• Do NOT multiply by 10!