crying

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What happens when you cry, exactly? A salty fluid chock full of protein, water, mucus and oil is released from the lacrimal gland in the upper, outer region of your eye. This fluid, better known as tears, then flows down the surface of your eye, across your face and smears your mascara.

Of course, not all tears are of the emotional variety. In fact, three types of tears exist, all with different purposes. Basal tears are omnipresent in our eyes. These constant tears are what keep our eyes from drying out completely. The human body produces an average of 5 to 10 ounces of basal tears each day. They drain through the nasal cavity, which is the reason so many of us develop runny noses after a good sobfest.

The second type is reflex tears, which serve to protect the human eye from harsh irritants such as smoke, onions or even a very strong, dusty wind. To accomplish this feat, the sensory nerves in your cornea communicate this irritation to your brain stem, which in turn sends hormones to the glands in the eyelids. These hormones cause the eyes to produce tears, effectively ridding them of the irritating substance.

The third type of tears is emotional tears It all starts in the cerebrum where sadness is registered. The endocrine system is then triggered to release hormones to the ocular area, which then causes tears to form. Emotional tears are common among people who see Bambi's mother die or who suffer personal losses.