After looking through my notes, I couldn't really find anything to teach you that I'm currently learning now. Today in lab I'll be busy looking at the digestive system of a cadaver and I didn't think that it would be a pleasant topic! So I decided to go off and find the answer to another question that I've have been wondering about for years.
Why do we yawn?
It’s widely assumed that yawning occurs because we are tired or bored or because we see someone else doing it, but there isn’t any hard evidence to support these beliefs.
Scientists do not purport to know all of the biological mechanisms of the yawn, but tend to agree that a yawn is an involuntary respiratory reflex, which regulates the carbon dioxide and oxygen levels in the blood.
Technically, a yawn is the reflex opening of the mouth followed by the deep inhalation and slow exhalation of oxygen.
The very act of yawning is but one of a number of involuntary reflexes controlled by the spinal and nerve centers.
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.
When one yawns, his or her alertness is heightened, as the sudden intake of oxygen increases the heart rate, rids the lungs and the bloodstream of the carbon dioxide buildup, and forces oxygen through blood vessels in the brain, while restoring normal breathing and ventilating the lungs.
Why do we yawn?
It’s widely assumed that yawning occurs because we are tired or bored or because we see someone else doing it, but there isn’t any hard evidence to support these beliefs.
Scientists do not purport to know all of the biological mechanisms of the yawn, but tend to agree that a yawn is an involuntary respiratory reflex, which regulates the carbon dioxide and oxygen levels in the blood.
Technically, a yawn is the reflex opening of the mouth followed by the deep inhalation and slow exhalation of oxygen.
The very act of yawning is but one of a number of involuntary reflexes controlled by the spinal and nerve centers.
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.
When one yawns, his or her alertness is heightened, as the sudden intake of oxygen increases the heart rate, rids the lungs and the bloodstream of the carbon dioxide buildup, and forces oxygen through blood vessels in the brain, while restoring normal breathing and ventilating the lungs.
Now how cute are yawning puppies!!?
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