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THE EYES — Part 3 of 3

Monday, November 2, 2015 @ 10:11 PM
Author: Amit Mathur


In the last part of our series in describing the eyes and how they function behind the scenes, we will examine how light is processed and the function of tears. Let’s begin!

Rods and Cones

We’ve already discussed the retina and how it has special cells called rods and cones which work to process light. Each one of your eyes has an astounding 120 million rods and an incredible 7 million cones. This is to help you see in great detail different shades of colour, as well as forms and shapes of items.

Rods detect the form and shape of items and specifically translate black, white and grey colours. Although rods can’t distinguish colour, they are what help you see things even when it’s very dark because they are so sensitive.

Cons, on the other hand, can distinguish colours, but require light for that. And within the cone family, there are three different types of cones. Each type of cone is specifically designed to distinguish a particular family of colours, red, green ad blue (the primary colours). These colours, as we learned early on, are the foundation of all other colours. The combination of these three different types of cones are what allow your eyes to see and detect the millions of different colours in the world.


Tears are an important part of the eyes and vision process. Tears are made from the lacrimal glands. The same way blinking helps keep dust and other little particles out of your eyes, tears do the same. When you blink, a small amount of tear fluid is secreted which also helps remove these small particles and ensures they don’t go into your eyes.

The other job tears have are to prevent your eyes from drying out. Once your lacrimal gland releases a bit of that fluid, it is then drained into your tear ducts. If you hurt your eye, have something in your eyes, your eyes will produce extra tears to protect the eye itself.

And of course, we all know that when we are sad, or laugh way too hard, we produce tears. Though crying doesn’t protect your eyes, tears are formed as a result of your brain sending a message to your glands.

Take Care Of Your Eyes

In the last few weeks, we’ve examined all the wonderfully complex parts of the eyes that work together, undetected, to allow you to see objects, colours, from a far and from close up. All in the blink of an eye, these things happen. But just as quickly, one can lose their vision. So it’s incredibly important to protect your eyes and treat them as you would any other part of your body. They are, in fact, more sensitive then other parts.

The things you should do to ensure you maintain healthy eyes, include maintaining a healthy lifestyle (including eating right and not smoking), protecting your eyes from UV rays, and wearing protective lenses when necessary, and having regular check ups with your eye care professionals to ensure everything is ok and there are no signs of disease or problems.

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