Tuesday, December 6, 2011

Wonder why we yawn ? Here's why.


When your body is low on oxygen, your mouth opens as wide as it comfortably can and tries to suck more air in. Yawning is a way to regulate the amount of carbon dioxide and oxygen in your blood.

Unfortunately, yawns are nearly impossible to stifle. Scientists speculate that the onset of a yawn is triggered either by fatigue or by sheer boredom as, at those times, breathing is shallow, and little oxygen is carried to the lungs by the oxygen-toting cardiovascular system.

0 comments:

Post a Comment