i no we yawn when were tired but what in our bodies make us do it
2006-12-17 09:43:44 · 28 answers · asked by girlsrule137 2 in Science & Mathematics ➔ Biology
Yawning increases the amount of oxygen you take in through your lungs - so when you are tired your brain decides to increase the oxygen levels by taking a really deep breath - the yawn.
2006-12-17 09:46:07 · answer #1 · answered by mark 7 · 1⤊ 3⤋
The commonly accepted belief is that we yawn when we are slightly deprived of oxygen. The lack of oxygen reaching the brain in turn may make us feel tired, although this is not a causal relationship.
There is a correlation between lack of oxygen and feeling fatigued, although I don't believe that the former always causes the latter. Perhaps when one is tired one does not breathe as quickly or deeply (as one would when sleeping or fully alert), thus the brain becomes a little starved for oxygen and needs a rapid intake. Note that it is possible to yawn with the mouth closed (if one does not want to appear rude in company of others). One will get the same feeling as if one yawned with the mouth gaping open. However, breathing through the mouth takes in more air rapidly than breathing through the nose.
2006-12-17 17:54:43 · answer #2 · answered by archangel2923 3 · 1⤊ 1⤋
A yawn (synonyms chasma, oscitation from the Latin verb oscitare, to open the mouth wide is a reflex of deep inhalation and exhalation associated with being tired, with a need to sleep, or from lack of stimulation. Pandiculation is the term for the act of stretching and yawning. Yawning is a powerful non-verbal message with several possible meanings, depending on the circumstances. It is also claimed to help increase the state of alertness of a person. The exact causes of yawning are still unknown.
2006-12-17 17:52:21 · answer #3 · answered by fluxpattern® 5 · 2⤊ 0⤋
sorry to burst everyone's bubble, but i saw a science show yesterday that investigated the reason why we yawn. it's true, about 20 years ago, scientist did believe that we yawn to increase the levels of oxygen in our body, but after doing tests, it was found that this was an unfounded theory. the guy talking about all of this on the program said that scientists are unsure as to why we yawn, but they think that it may be more of an empathy thing.... which is why people say that yawing is contagious..... it's a way of communicating at a basic level. i swear that this is true..... it was on one of the discovery channels last night.
2006-12-17 18:08:03 · answer #4 · answered by Anonymous · 0⤊ 0⤋
Low oxygen levels in the boby when tired causes us to yawn.
2006-12-17 18:05:29 · answer #5 · answered by Anonymous · 0⤊ 1⤋
When Yawn we want to sleep
2006-12-17 17:52:23 · answer #6 · answered by Anonymous · 1⤊ 1⤋
It's a way of catching up on your oxygen intake. When you're tired or bored your breathing becomes more shallow, so you have less air in circulation. When this happens your brain sends you the signal to yawn and you take in a big gulp of air at once to catch up, whilst simultaneously dispelling carbon dioxide build up.
2006-12-17 17:47:56 · answer #7 · answered by Anonymous · 1⤊ 3⤋
We yawn when we see the same stupid question on Yahoo! Answers. No offence, but this question is boring me now.
2006-12-17 17:56:19 · answer #8 · answered by b97st 7 · 0⤊ 1⤋
When you are tired you don't breath as deeply as you should. You body signals you to yawn because it needs some oxygen...
2006-12-17 17:46:40 · answer #9 · answered by capnemo 5 · 2⤊ 3⤋
when we get tired our body doesn't take in as much oxygen sometimes therefore we yawn to take in more oxygen
2006-12-17 17:46:54 · answer #10 · answered by sarah_newby86 2 · 1⤊ 2⤋