why does the body respond with tears when you are sad?

Question

like people normally cry when sad.. or really happy.. why does the body respond to these emotions with tears?

Answer 1

One line answer is "Evolutionary Intelligence".

But for explaining this we need to look at various natural phenomenon happening in global scale as well as microscopic levels.

Let us start thinking by asking questions similar to yours:
1. Why we eat when hungry?
2. Why we laugh when listening to a joke?
3. Why make merry when happy?
4. Why the wind blows from sea to land and vice-versa?

and so on.

Yes our body has developed finest mechanisms called hormones, and learned to use enzymes, co-enzymes which are catalysts.

So it is all the bio-chemical changes that you see, feel and experience as tears, joy, angry, sexual impulses and so on. Just that is a bio-chemical reaction or as I said, "Evolutionary Intelligence to express our feelings and feel others' as well".

These are the marks of higher stages of social adaptations getting expressed in individuals. An evolutionary genius in us to make and allow us to live in societies to appreciate others and ourselves. Without them we are just individuals and not social animals.

Answer 2

Tears are a liquid produced by the body's process of lacrimation to clean and lubricate the eyes. The word lacrimation may also be used in a medical or literary sense to refer to crying.

Crying or weeping (psychic tears): The third category, generally referred to as crying or weeping, is increased lacrimation due to strong emotional stress, depression or physical pain. This practice is not restricted to negative emotions; many people have been known to cry when extremely happy or when they are laughing. In humans, emotional tears can be accompanied by reddening of the face and sobbing — cough-like, convulsive breathing, sometimes involving spasms of the whole upper body. Tears brought about by emotions have a different chemical make up than those for lubrication. The limbic system is involved in production of basic emotional drives, such as anger, fear, etc. The limbic system, specifically the hypothalamus, also has a degree of control over the autonomic system. The parasympathetic branch of the autonomic system controls the lacrimal glands via the neurotransmitter acetylcholine through both the nicotinic and muscarinic receptors. When these receptors are activated that the lacrimal gland is stimulated to produce tears.

In nearly all cultures, crying is seen as a specific act associated with tears trickling down the cheeks and accompanied by characteristic sobbing sounds. Emotional triggers are most often anger and grief, but crying can also be triggered by sadness, joy, fear, laughter or humor, frustration, or other strongly-experienced emotions.

http://en.wikipedia.org/wiki/Tears

Answer 3

Maybe all that emotion causes chemicals in the Brain to release certain Neurotransmitters that then cause a reaction that coincides with the lacrimal gland in our eyes, so when we feel sad, it is activated and we start to cry. Sort of like flight or flight response, when you are anxious or scared your body signals to tense up your muscles and your pupils dilate and your heart beats faster. When you're happy, You release seratonin.

Answer 4

maybe something to do with the body being in distress and like dilation of blood vessels the body signals to whatever and produces tears to relieve distress in the eyes or something or other. i'm pretty sure it's distress or it could be the other way around, tears being a way to "cue" the mind that a sad event is occurring, it works with smiling, so it might be the same with tears. just a thought :/

Answer 5

When you get upset and emotional, your parasympathetic nervous system kicks in to try and calm you down. As a result, your nervous system triggers many different physical reactions. Among these reactions is the activation of the tear ducts, thus you cry. =)

Answer 6

the “West is now celebrating the loss of existence of somebody who, in spite of the undeniable fact that misled and incorrect-minded, replaced right into a man or woman who replaced into keen to combat for the poorest and the main susceptible human beings contained in the international to the very end of his existence.” Noam Chomsky is not any form of "respectable spokesman" for Liberals, Progressives or The Left. He speaks for himself - no longer in basic terms like the lockstep speaking heads on the main suitable from Krauthammer and Wills to Limbaugh, Beck, Hannity and O'reilly who all look for advice from to declare the comparable factor on the comparable time, following the orders of their masters; Rupert Murdoch and The Koch brothers.

Answer 7

To show others that you're sad/happy/scared?

Not quite sure