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Is 20/20 eyesight perfect? Random eye facts

Updated on September 27, 2012
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What causes redeye?

Eyes appear as red dots in photos sometimes because the flash from cameras reflect off of the layer of blood vessels between the reteina and sclera (whites) of the eyes. This usually occurs when the lights are dim and the eyes are directed straight at the camera.

Why do all newborn babies have blue eyes?

The color of the iris gives human eyes their color. Melanin, the dark pigment in the iris, determines the color. The pigment in newborns is concentrated in the folds of the iris. When a baby is a few months old, the melanin shifts to the iris surface, giving a baby its permanent eye color.

What is 20/20 vision?

It means the eye can see clearly at 20 feet what a normal eye can see at that distance; it doesn't necessarily mean perfect vision. 20/15, for instance, is even better than 20/20.

What are those little lights you see with your eyes shut?

These are phosphenes, which come about when your shut your eyes tight. The retina is stimulated by the pressure on your eyeball.

Are there more nearsighted or farsighted people?

Nearly 30% of Americans are nearsighted and 60% farsighted.

How often do you blink?

On the average, the human eye blinks once every five seconds (12 per minute), or 17,000 times a day, or 6.25 million times a year!

How do colors affect one's moods?

Each color has its own wavelength. The wave bands stimulate chemicals in the eye that send messages to the pituitary and pineal glands, which regulate hormones and other physiological systems. This affects moods and can speed up heart rates and brain activity.

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      Veryhot! 5 years ago

      The human eye has blood in it.

    • profile image

      cookie monster 6 years ago

      milk is awesome idont care about eyesight

    • pinkhawk profile image

      pinkhawk 7 years ago from Pearl of the Orient

      ...great facts about the eyes, I learn something new and sensible. thank you ma'am! :)