This is a powerpoint targeted toward people looking to understand their eyes better, specifically kids who are getting glasses for the first time and really don't understand why.

1. Understanding Your
Eyes
Project by: Jena Mahoney

2. Parts of the Eye
Pupil- the round black dot in the middle of your eye
Iris- the colored part of your eye that is around the black
dot
Cornea- a clear bubble that covers the iris and pupil
Aqueous Humor- clear fluid inside of the cornea
Lens- an oval shaped body behind the pupil and iris
Suspensory Ligament- little strings that are pulled tight to
hold the lens in place
Ciliary Body- at the ends of the strings, produces aqueous
humor
Vitreous Humor- clear jelly that fills your eye
Sclera- the outer protective coat of your eye, “the white stuff”
Choroid- layers of blood vessels underneath the sclera

3. Parts of Your Eye (continued)
Retina- the sensory membrane underneath the blood vessels
Fovea- a dip in the retina that only contains cones
Optic Nerve- a cord at the back of your eye that is a messenger for
your brain
Central Artery- a blood vessel inside the eye that is solely for
nutrition
Vein of the Retina- forms with the central artery to drain the retina
Optic Disc- a circle at the back of your eye that the optic nerve
attaches to the retina through

4. How Your Eyes Work (Our own personal camera)
• Once the light hits these rods and
cones on the retina (the sensory
membrane) the image appears
upside down.
• The optic nerve carries this image
to the visual part of the brain, and
it puts together the image.
• This all happens in 13 milliseconds!
- Light enters the eye through the cornea. (That clear bubble in front of the black dot and colored circle.)
- The black dot, the pupil, is actually a hole that opens and closes to allow certain amounts of light in the eye.
- After the light enters the eye, it passes through the hole. (The amount is regulated by the colored part of your eye.)
- The light then hits the lens and projects the light image onto the retina, which is full of thousands of rods and cones.

5. Things That Can Go Wrong
Amblyopia (lazy eye)- a vision development that causes the optic nerve to
not pick up vision as well, could cause permanent vision loss.
Astigmatism- caused by an irregular cornea, causes blurred vision at all
distances.
Color blindness- light sensitive cells in the retina fail to respond
appropriately to variations in wavelengths of light, usually only affects
males.
Dry eye syndrome- the lacrimal gland doesn’t produce enough tears, or
not enough oil being produced causes excess evaporation of tears.
Hyperopia (Farsightedness)- light rays entering the eye focus behind the
retina, rather than on it, your eye is shorter than the average person,
images are hard to see if closer up.
Myopia (Nearsightedness)- light entering the eye does not focus properly
on the retina, your eye is elongated, and objects are hard to see from
farther away.

6. Why People Need Glasses
If you are nearsighted, farsighted or have astigmatism, you are in luck because it
can be corrected easily with glasses!
For nearsightedness, the lens on the glasses bend the light rays outwards to
normalize the eyeball due to its extended length.
For farsightedness, the lens on the glasses bend the light rays inwards before it
reaches the lens of the eye, fixing the shortness of your eye.
For astigmatism, you use bifocals, which bend the light both inwards and
outwards, depending on the angle that you look in to them.
Having glasses is normal and not geeky at all, many famous people wear them,
(Justin Timberlake, Harry Potter, Johnny Depp & many more), along with 75%
of the whole population!

7. Hopefully now you understand your eyes a little bit better now, so don’t get discouraged if your
eye doctor tells you that you have eye problems, they are perfectly normal and most of the time
can be corrected!