Please tell me why....
2007-06-24 10:38:03 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Biology
The reason why we do yawn is because our body is telling that we need more oxygen.
2007-06-24 10:41:16 · answer #1 · answered by Katherine N 4 · 1⤊ 1⤋
To expel co2 from our lungs that has gathered and collected there. Well that was one reason i was told at school. The infectious yawn that when one person yawns someone sees it and then they yawn i have no idea!
2007-06-24 17:41:24 · answer #2 · answered by Seventy_Times_7 2 · 1⤊ 1⤋
Nobody knows for sure really. There are a lot of hypotheses but scientists are still out on a definite cause or reason.
The Mythbusters did a cool show on it to see if it really was contagious.
http://en.wikipedia.org/wiki/Yawn#Hypothesized_causes_of_yawning
2007-06-24 17:41:45 · answer #3 · answered by Lady Geologist 7 · 0⤊ 1⤋
Because there's not enough oxygen to the brain, or the lungs. I forgot which one. That's why when you're tired, you yawn, because your body's breathing slows down. Or if you hold your breath and start breathing again you're subject to start yawning.
2007-06-24 17:41:50 · answer #4 · answered by Fangirl ♥♥ 5 · 1⤊ 1⤋
good question ..
and another one is WHY is yawning contagious ?
2007-06-28 07:33:35 · answer #5 · answered by ll_jenny_ll here AND I'M BAC 7 · 0⤊ 0⤋
i believe is the lack of Oxygen in the body and a great build up of CO2 in our body causes this
2007-06-24 18:34:51 · answer #6 · answered by T.B. 2 · 0⤊ 1⤋