Why do we yawn?

Question

Is it reall contagious?

Answer 1

It's a good way to let people see what color underwear you're wearing.

Answer 2

There is a balance of oxygen and carbon dioxide in you're lungs. When we hyperventilate you may see some one breath into a bag to absorb More C than O. When the opposite is true we yawn to release theC.

Answer 3

its not because we are sleepy. its because the oxygen in our blood dropped and we need it immediately. once we get tired you get sleepy and your breathing slows down but you are not slowing down as far as your day goes. so your body needs more oxygen but you are breathing shallow and slow so you begin to yawn. and it is a bit contagious. once you see someone yawn you might yawn right after. and no, there is no cure for that...lol

Answer 4

Yawn in a group of people... see how catchy it is.

I was told in school that we yawn because we get tired and stop breathing as deep as normal... and it is our bodies way of getting more oxygen. This, of course, is debate-able but it came from a medical course...

Answer 5

i learned in psychology that it bring oxygen to the brain and also stretches the neck muscles to help us stay awake longer. they also said its contagious because the mind reacts to the respond of other people ,so basically if someone in class yarns from boredom you will to because the mind triggers something making you think you are bored to .weird dont know if its true just saying what the book said.

Answer 6

The most plausible explanation, and the one that is taught in medical school, is that we yawn because oxygen levels in our lungs are low.

Answer 7

When we get tired our respiration rate drops(meaning we breath less) We yawn to get oxygen in.

Answer 8

We yawn because we have a lack of oxygen. Not because we are tired.

Answer 9

lack of oxygen to the brain causes you to yawn

Answer 10

Bring oxygen to the brain.

Answer 11

they say its lack of oxygen but im real tired. *yawn* now tell me no one else couldnt help but yawn too.