Sight helps us navigate the world all around us. In a single glance, our eyes work with our brains to tell us the size, shape, color, and texture of an object. They let us know how close it is, whether it's standing still or coming toward us, and how quickly it's moving. The eyes are small compared with most organs, but their structure is incredibly complex.
Only part of the eye is visible in a person's face. The whole eye (the eyeball) is about the size and shape of a ping-pong ball. All parts of the eye are extremely delicate, so our bodies protect them in several ways. The eyeball sits in the eye socket (also called the orbit) in the skull, where it is surrounded by bone. The visible part of the eye is protected by the eyelids and the eyelashes, which keep dirt, dust, and even harmful bright light out of the eye. Tears help protect against infection. With each blink, our eyelids spread a layer of mucus, oil, and tears over the cornea, which covers the eye.
Vision is the process by which images captured by the eye are interpreted by the brain, and the visible part of the eye is where the process of sight begins. On the front surface of the eye is the see-through, circle-shaped cornea. You can't see a person's cornea the way you can see the colored part of the eye behind it — the cornea is like a clear window that focuses light into the eye. When focused light is projected onto the retina, it stimulates the rods and cones. The retina then sends nerve signals are sent through the back of the eye to the optic nerve. The optic nerve carries these signals to the brain, which interprets them as visual images. The portion of the brain that processes visual input and interprets the messages that the eye sends is called the visual cortex.
You’ve had your eyes since birth. You may think you know everything about them, but here are fun facts you may be unfamiliar with:
·
80%
of vision problems worldwide are avoidable or even curable.
·
Around
the world, about 39 million people are blind and roughly 6 times that many have
some kind of vision impairment.
·
Doctors
have yet to find a way to transplant an eyeball. The optic nerve that connects
the eye to the brain is too sensitive to reconstruct successfully.
·
Each
of your eyes has a small blind spot in the back of the retina where the optic
nerve attaches. You don’t notice the hole in your vision because your eyes work
together to fill in each other’s blind spot.
·
Eyes
heal quickly. With proper care, it only takes about 48 hours for the eye to
repair a corneal scratch.
·
Newborns
don’t produce tears. They make crying sounds, but the tears don’t start flowing
until they are about 4-13 weeks old.
·
Out
of all the muscles in your body, the muscles that control your eyes are the
most active.
·
Seeing
is such a big part of everyday life that it requires about half of the brain to
get involved.
·
Some
people are born with two differently colored eyes. This condition is
heterochromia.
·
The
average blink lasts for about 1/10th of a second. You blink about 12 times
every minute.
·
The
cells in your eye come in different shapes. Rod-shaped cells allow you to see
shapes, and cone-shaped cells allow you to see color.
·
Your
eyes are about 1 inch across and weigh about 0.25 ounce.
“The eyes are one of the most powerful tools a
woman can have. With one look, she can relay the most intimate message. After
the connection is made, words cease to exist.” (Jennifer
Salaiz)[i]
 |
| Inside of Eye |
[i] Sources used:
·
“Eyes: 15 Facts You Probably Didn't know about them
“by vsp
·
“Eyes” Reviewed
by: Jonathan H. Salvin
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