Yawning

Yawning is an involuntary action that everyone does. We start it even before we are born and most creatures on the planet yawn.  Research shows that 11-week-old fetuses yawn. There are many parts of the body that are in action when we yawn. 'Why do we yarn' is not exactly known however there are various theories.

One is that when we are bored or tired, we just don't breathe as deeply as we usually do. As this theory goes, our bodies take in less oxygen because our breathing has slowed. Therefore, yawning helps us bring more oxygen into the blood and move more carbon dioxide out of the blood.

Another theory is that yawning stretches the lungs and lung tissue. Stretching and yawning may be a way to flex muscles and joints, increase heart rate, and feel more awake.

Its said yawning is a protective reflex to redistribute the oil-like substance called surfactant  that helps keep lungs lubricated inside and keeps them from collapsing. So, if we didn't yawn, according to this theory, taking a deep breath would become harder and harder — which would not be good.


Yawning is
Its a subconscious human behaviour. Next time you're in a meeting, try this little experiment: Take a big yawn, cover your mouth out of courtesy, and watch and see how many people yawn. There's a good chance that you'll set off a chain reaction of yawns. Before you finish reading this question of the day, it's likely that you will yawn at least once.

Some Interesting Yawning Facts

• The average yawn lasts about six seconds.
• Your heart rate can rise as much as 30 percent during a yawn.
• 55 percent of people will yawn within five minutes of seeing someone else yawn.
• Blind people yawn more after hearing an audio tape of people yawning.
• Reading about yawning will make you yawn.

Yawning can also be a powerful non-verbal message with several possible meanings, depending on the circumstances..heh...

Hope teachers in the school understand this and not shout at students for yawning in the class.....