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THE HUMAN EYE


Harmony STEM Project - The Human Eye










 

The human eye is a slightly asymmetrical sphere, around an inch in diameter. Out of all the organs in the human body, the eye has been called one of the most complex organs. Our eyes allow us to see the things around us and without them we would lose our sense of sight. As long as there is light, we are able to see every time we open our eyes. The human eyes are very important; however, have you ever wondered how we’re able to see? There are many parts of the eye working together to allow us to have vision and each part has a significant role.

To be able to see, light is needed. This is due to the fact that the light rays reflected off an object enter the eye and go through the cornea, pupil, lens, and vitreous humor. The light rays are then projected as an upside down image on the retina. Both eyes have these two reversed images, which are sent to the brain through the pair of optic nerves as electrical signals. These signals are the created once the retina converts the light rays. There are many parts that make up the eye, but the parts of the eye that we can see are the iris, pupil, cornea, sclera, and conjunctiva and the parts of the eye that we cannot see are the choroid, lens, vitreous body, retina, optic nerve, lacrimal gland (tear gland), and eye muscles. When anything happens to these parts problems in vision could occur. Two very common medical conditions are nearsightedness and farsightedness. People who have nearsightedness, which is also known as myopia, have difficulty seeing distant objects, but can clearly see objects that are near. Farsightedness, or hyperopia, is the complete opposite of myopia. People with hyperopia have a difficulty seeing objects that are near clearly, but can easily see objects that are at a distance.


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