7 AMAZING FACTS ABOUT YOUR EYES

1)   Did you know eye colour is controlled by the  level of MELANIN in your iris  ?

•  Brown eyes have more melanin ( a dark brown pigment )  in their iris.
• Blue eyes have less  melanin , which allows collagen ( which is blue ) , to show through.

2)   If you have blue eyes , then you share a common ancestor with every other blue-eyed person in the   world.

• The first person ever to have blue eyes lived sometime between 6,000 and 10,000 years ago. Before then , all people had brown eyes.

3)   Your eyes contains 107 millions of cells which are sensitive to light.

• 7 million "cones (cell in eyes)" help you to see colour and details. 
• 100 million cells called "rods" help you to see better in dark.

4)   Did you know that 20/20 vision just means your vision is "normal" ?

• Eye doctors have determined what people should "normally" be able to read on a chart from 20 feets away.

5)   If you wore glasses which flipped images upside down, your brain would correct your vision.

• Although you had see things upside down for few days , your brain would eventually adapt, and make sure that  you see everything the right way up.

6)   On average , you blink 17 times per minute , 14,280 times in 14 hours in a day and 5.2 million times a year.

• You blink more when you are talking.
• you blink less when you are reading , which is why your eyes get tired quickly.

7)   They say "in the blink of an eye" because it's fastest muscle in your body.

•  a blink typically lasts 100-150 milliseconds.
• I's possible to blink 5 times in a second.