why do we produce tears when we cry

This is an article from, a series for children. The Conversation is asking kids to send in questions theyБd like an expert to answer. All questions are welcome Б serious, weird or wacky! Why do tears come out of our eyes when we cry? Б Grace, age 9, Melbourne
Hi Grace, thank you for a great question. We cry, or make tears,. First, we need tears to keep our eye healthy, so you can say that our eyes cry a little bit all through the day. These types of tears usually donБt come out of our eyes. Tears do come out of our eyes when we are emotional Б either very sad or happy Б or when our eyes are irritated by something, like a bit of dust that gets into our eyes or when we cut an onion. Tears are needed for our eyes to work properly. Your eye has special parts Б called glands Б that make tears all day. Normally they only produce a tiny amount of tears Б less than half a teaspoon per day. Tears are mostly water and a little bit of salt, but they also have some oil, mucus and chemicals called enzymes that kill germs. A small amount of oil in tears stops them from evaporating or leaking out of our eyes. If we didnБt have oil in our tears, it would make our eyes really dry and sore. When you blink, the eyelid spreads the tears around your eye and mucus helps the tears stick to the eyeball. Any tears left over drain through a special drainage system that goes through to your nose.


When we cry Б and I hope you donБt cry too often Б we make more tears than the eye can hold. This is because the largest tear gland can switch on and produce a lot of tears at once, just like a little fountain. Read more: The part of the brain that switches on the Бtear fountainБ receives signals from the part of your brain that controls your emotions. When this happens, the eye can produce more than half a cup of tears in minutes. This is way too much for the eye to hold and our drainage system goes to work. Remember that this drainage system goes to our noses? ThatБs why when you cry you may notice your nose starts running. These are these extra tears. If you cry really hard, then there are far too many tears even for that drainage system to remove, so the tears start falling out of our eyes. According to psychologists, only humans cry as an emotional response. , Psychologists believe that crying because of emotions is something only humans do. Most of us cry sometimes because we are really sad. Some of us also cry when we are happy. We havenБt figured out exactly why we cry when we are emotional, but we do know that the chemicals found in emotional tears are. Some scientists believe that these chemicals. Read more: There are also some strange conditions that can make people cry. Some people cry when they eat or even just think about food.


This is called. It is named that said crocodiles pretend to cry to trick their prey into coming closer to them. Crocodile tears syndrome may happen after someone has been in an accident and broken some bones in their face. As the face heals, some body parts called nerves repair themselves in the wrong way. Nerves that made your mouth water when you smell good food get mistakenly connected to the tear gland instead. Afterwards when that person eats or smells something delicious that makes their mouth water, they start to cry. Hello, curious kids! Have you got a question youБd like an expert to answer? Ask an adult to send your question to us. You can: * Email your question to curiouskids@theconversation. edu. au * Tell us on by tagging with the hashtag #curiouskids, or * Tell us on Please tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We wonБt be able to answer every question but we will do our best. Let us count the ways. Tears well up in people s eyes for a slew of reasons. A teardrop running down the cheek is the ultimate symbol of sadness, but people may also cry because they just cut an onion, or maybe they re trying to blink out a rogue eyelash. For the most part, tears help maintain healthy eyes, experts told Live Science.


For instance, basal tears flow continuously from the lacrimal glands, or the tiny almond-shaped structure in the inside corner of the eye. When you blink, basal tears clean and lubricate the eyes. This makes the eyes outer surface smooth, and, according to the. Moreover, reflex tears, or those t hat happen unconsciously, help clear the eyes of irritants, including specks of dust and the sulfur-based gas that s produced when a knife slices a raw onion, said Andr Silva, a doctoral student of psychology at the University of Minho in Portugal. [ Emotions can also trigger tears in humans. These emotional tears (also called psychic tears) can serve as a means of nonverbal communication, Silva said. Babies cry to signal to their mothers [that] something s up, Silva told Live Science in an email. It s a pure attention call. Some people think that babies are capable of manipulating adults by crying, but that idea is false, Silva said. This is misleading, as a baby is not conscious of being manipulative: In a way, we can consider these tears as being somewhere between basal/reflex tears and emotional tears. As people grow older, they begin to use their tears to express emotion, such as happiness or sadness. These tears may promote compassion and empathy in others, Silva said. But beware of people who may use their tears to manipulate others, he said. Some sensitive people may be easily manipulated through the crying of others, and may easily shed tears that can also be used by others to manipulate them, he said.


So, emotional tears have both advantages and disadvantages. It s a powerful communication device and a powerful manipulative device, Silva said. Crying also makes it hard for some people to mask their feelings when they re in the middle of an extreme emotional state, he said. Basal, reflex and emotional tears each have their own chemistry, studies show. Basal tears have three layers: a thin mucus layer that sits directly on the eye, a watery layer in the middle and a thin oily layer on top that prevents the tear from evaporating, a site that shares free educational videos. Reflex tears also have these three layers, but these tears have a larger watery portion and higher levels of antibodies that can stop harmful microorganisms as compared to basal tears, TedEd reported. Emotional tears can contain higher levels of stress hormones, including leucine enkephalin, an endorphin and natural painkiller, TedEd said. This may explain the cathartic effect of a good cry which is still debated in case you need to shed a few tears. Additional reporting by Ben Mauk, Life s Little Mysteries Contributor. Follow Laura Geggel on Twitter @LauraGeggel. Follow Live Science s Life s Little Mysteries @LLMysteries, Facebook Google+.

  • Views: 39

why do you cry when you chop onions
why do we have tears when we cry
why do we get tears when we cry
why do tears come when we are sad
why do tears come out when you cry
why do tears come when we cry
why does yawning make your eyes water