Learning about the Eye

Photo by Perchek Industrie on Unsplash

By Nilay Bhavsar 

Swimming, running, sleeping, reading, and watching TV. All of these are activities that everyone
enjoys, but what is common about all of them: they require function from the eye. Yes, believe it
or not, even when we are sleeping, our eyes are active. During the sleeping process, our eyes
undergo rapid eye movement, a period where the eye rolls around behind the eyelids causing
the body to sooth and fall asleep.

Now that we know how important the eyes are in our daily life, let's dissect each part and
analyze why we can do these simple functions.

The eye is made up of 4 photoreceptors, a pigment responsible for light conversion. In the eye,
there are short-wavelength cones, medium-wavelength cones, and long-wavelength cones, with
each corresponding to a specific color.The fourth photoreceptor is a rod, a structure used to
determine black and white light and the transfer of that color. All of these pigments are very
important in light conversion as without them, images wouldn’t be seen. These pigments are
located in the main area/most important part of the eye called the retina.

The retina is the main area of activity in the eye, where light is transferred and images are read.
In addition to being the location of the photoreceptors, the retina is home to other nerve cells
which receive/gather visual ideas. The retina uses this visual ideas/information and sends it to
the brain, causing sight. The retina is in the back of the eye where the nerves and the fibers of
the eye are connected to the brainstem and spinal cord. Without it, a disease called macular
degeneration is formed where the brain will not receive any signals and can result in vision loss.
Another fascinating and crucial part of the eye is the cornea. The cornea is the layer directly in
the front of the eye. The cornea’s role in the eye is like a window to a house; it guards the eye
and allows a certain amount of light to enter. The cornea is mostly water, with roughly three
quarters of it filled with this liquid and the rest is composed of collagen. Collagen is the main
structural protein in the human body.

The iris is a fundamental structure of the eye and is just as important as the retina. The iris is the
colored part of an eye’s inner cornea. Its role is to regulate the amount of light entering the
retina by opening/closing the lens when necessary. Its regulation is the crucial part in helping
the retina and the cornea send signals. If damaged, it can cause color blindness and results in
shut eyelids, which can affect sleep.
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The eye is the body’s unsung hero, working behind the scene to help other systems. Without the
eye, not only will our vision be lost but our other systems, like the nervous system, will be
impaired. The eye is not only very important, it also is very complex, as the processes during
night are perplexing.