Login

Join for Free!
114820 members


why do we yawn???

For discussing the functions of different structures of all organisms.

Moderator: BioTeam

why do we yawn???

Postby VeenaandNivyah » Wed Mar 01, 2006 1:48 pm

Hey All,:D
my teacher was goin on and on and as usual I was yawning away to glory. :lol: I wondered whether yawning was only realated to feelin sleepy or whether it had more to it. :?
If there is, do let me know.
thanx in advance.
Veenaandnivyah:)
User avatar
VeenaandNivyah
Coral
Coral
 
Posts: 105
Joined: Thu Sep 15, 2005 1:31 pm
Location: India (unity in diversity)

Postby gubbin » Wed Mar 01, 2006 5:12 pm

I think that we yawn because of your lungs acting wierd after a long day. Like they are trying to even out or something. but honestly...I dont know :oops:
gubbin
Garter
Garter
 
Posts: 1
Joined: Wed Mar 01, 2006 5:10 pm

Postby Poison » Wed Mar 01, 2006 5:55 pm

You feel sleepy so your metabolism slows down and you take in less O2. But you are still awake and you need more O2. So you yawn to get more.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.
User avatar
Poison
Inland Taipan
Inland Taipan
 
Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey


Postby Abstract » Wed Mar 01, 2006 9:10 pm

Don't fetuses in the womb yawn? If that's the case, I can't imagine it would be to get more O2.
Abstract
Garter
Garter
 
Posts: 12
Joined: Tue Aug 02, 2005 10:23 pm

Postby kiekyon » Thu Mar 02, 2006 3:43 am

i get this from wikipedia....

A long-standing hypothesis is that yawning is caused by an excess of carbon dioxide and lack of oxygen in the blood. The brain stem detects this and triggers the yawn reflex. The mouth stretches wide and the lungs inhale deeply, bringing oxygen into the lungs and hence to the bloodstream. It is almost certain however, that this hypothesis is not correct. A more recent hypothesis is that yawning is used for regulation of body temperature. Another hypothesis is that yawns are caused by the same chemicals (neurotransmitters) in the brain that affect emotions, mood, appetite and other phenomena. These chemicals include serotonin, dopamine, glutamic acid and nitric oxide. As more of these compounds are activated in the brain, the frequency of yawning increases. Conversely, a greater presence in the brain of opiate neurotransmitters such as endorphins, reduces the frequency of yawning. Patients taking the serotonin reuptake inhibitor Paxil (Paroxetine HCl) have been observed yawning abnormally often.

Another theory is that yawning is similar to stretching. Yawning, like stretching, increases blood pressure and heart rate while also flexing many muscles and joints. Some have observed that if you try to stifle or prevent a yawn by clenching your jaws shut, the yawn is unsatisfying. As such, the stretching of jaw and face muscles seems to be necessary for a good yawn.

The yawn reflex is often described as contagious: if one person yawns, this will cause another person to "sympathetically" yawn. The reasons for this are unclear; however, recent research suggests that yawning might be a herd instinct. Other theories suggest that the yawn serves to synchronize mood behavior among gregarious animals, similar to the howling of the wolf pack during a full moon. It signals tiredness to other members of the group in order to synchronize sleeping patterns and periods of activity. It can serve as a warning in displaying large, canine teeth, thus proclaiming, "don't attack while I am sleeping..." The contagion of yawning is interspecific (i.e., try yawning in front of your dog). Ironically, yawning in public is generally regarded as impolite in the West, but came into fashion in polite French society for a brief period in the late 18th century. Oddly, sometimes sympathetic yawning may be caused by simply looking at a picture of a person or animal yawning, or even seeing the word "yawn".

Adelie Penguins employ yawning as part of their courtship ritual. Penguin couples face off and the males engage in what is described as an "ecstatic display," their beaks open wide and their faces pointed skyward.
kiekyon
Coral
Coral
 
Posts: 410
Joined: Thu Feb 16, 2006 6:10 am
Location: Malaysia

Postby VeenaandNivyah » Thu Mar 02, 2006 11:03 am

thanx...so next time i yawn, i'll make sure i remeber all that. oh..i just yawned, that reminds me...how come I forgot to think abt the science behind yawning...guess it's really impossile considering its me :lol:
User avatar
VeenaandNivyah
Coral
Coral
 
Posts: 105
Joined: Thu Sep 15, 2005 1:31 pm
Location: India (unity in diversity)

Postby Poison » Thu Mar 02, 2006 8:20 pm

Abstract wrote:Don't fetuses in the womb yawn? If that's the case, I can't imagine it would be to get more O2.

I don't know if fetuses yawn or not. But I can not get it, the fetus do not inhale air, so how can you call it yawning.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.
User avatar
Poison
Inland Taipan
Inland Taipan
 
Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey

Postby kiekyon » Fri Mar 03, 2006 7:59 am

well, i am sure i read somewhere that someone managed to see a fetus 'yawning' through ultrasonogram. however i think the fetus just open its mouth for a few second for some unknown or perhaps for no reason at all. they are not really taking in air or something
kiekyon
Coral
Coral
 
Posts: 410
Joined: Thu Feb 16, 2006 6:10 am
Location: Malaysia

Postby MrMistery » Fri Mar 03, 2006 6:48 pm

totally stupid... The fetus keeps his mouth open, that doesn't mean it is yawning. He drinks the amniotic fluid, so maybe that is why he keeps it's mouth open.
I would like to have a word with the author of your book
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter
User avatar
MrMistery
Inland Taipan
Inland Taipan
 
Posts: 6832
Joined: Thu Mar 03, 2005 10:18 pm
Location: Romania(small and unimportant country)

Postby Abstract » Sat Mar 04, 2006 3:31 am

Abstract
Garter
Garter
 
Posts: 12
Joined: Tue Aug 02, 2005 10:23 pm

Postby kiekyon » Sat Mar 04, 2006 9:45 am

in the study referred to by abstract

"yawning was represented by isolated mouthing movements and consisted of slow opening of the mouth with simultaneous downward movements of the tongue........"

it doesn't suggest any intake of air..
kiekyon
Coral
Coral
 
Posts: 410
Joined: Thu Feb 16, 2006 6:10 am
Location: Malaysia

Postby kiekyon » Sun Mar 05, 2006 7:58 am

MrMistery wrote:.. The fetus keeps his mouth open, that doesn't mean it is yawning...


this is from the dictionary
yawn
1. To open the mouth involuntarily through drowsiness, dullness, or fatigue; to gape; to oscitate. "The lazy, yawning drone." "And while above he spends his breath, The yawning audience nod beneath." (Trumbull)

2. To open wide; to gape, as if to allow the entrance or exit of anything. "'t is now the very witching time of night, When churchyards yawn." (Shak)

3. To open the mouth, or to gape, through surprise or bewilderment.

4. To be eager; to desire to swallow anything; to express desire by yawning; as, to yawn for fat livings. "One long, yawning gaze."

so, i think u can say the fetus are really yawning.....
kiekyon
Coral
Coral
 
Posts: 410
Joined: Thu Feb 16, 2006 6:10 am
Location: Malaysia

Next

Return to Physiology

Who is online

Users browsing this forum: No registered users and 0 guests

cron