男友太凶猛1v1高h,大地资源在线资源免费观看 ,人妻少妇精品视频二区,极度sm残忍bdsm变态

您現(xiàn)在的位置: Language Tips> Easy English> Odd Question  
 





 
我們?yōu)槭裁创蚬?/div>
[ 2007-06-27 15:51 ]

打哈欠是一個(gè)人人都會(huì)、一旦啟動(dòng)就無(wú)法中途停止的動(dòng)作。幾乎所有動(dòng)物都會(huì)打哈欠。貓咪睡前睡后哈欠連連,一副自我感覺(jué)良好的樣子;大大小小的猩猩都會(huì)打哈欠,有的還會(huì)用手蓋住嘴巴,以免被別的猩猩誤解為侵略行為。母親肚子里的胎兒也會(huì)打哈欠.那么,哈欠究竟是怎么回事呢?下面這篇文章也許能給您一點(diǎn)啟示。

Almost everyone yawns when they feel sleepy. So do most animals.But we don't completely understand why people and animals for that matter, 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 notpurportto know all of the biological mechanisms of the yawn, but tend to agree that a yawn is aninvoluntaryrespiratory 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 deepinhalationand slowexhalationof oxygen.

The very act of yawning is but one of a number of involuntary reflexes controlled by thespinaland 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-totingcardiovascular 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.

This quite plausible theory of yawningfalls short ofexplaining many aspects of yawning. Scientists explain away the "contagious" nature of yawning, that is when one person's yawn triggers another nearby to yawn, as due to the power of suggestion, but areat a losswhen attempting to explain why yawning occurs excessively in patients with lowerbrainstemdamage or with multiplesclerosis.

Other unlocked mysteries include whyfetusesin thewombyawn, when it is a well-known fact that they do not intake oxygen into their lungs until after live birth, or why individuals with high concentrations of oxygen in their blood streams yawn.

Until these questions are answered, do not assume that a person who yawns in your presence is bored with what you are saying, or suffers from exhaustion. Simply be pleased that he or she is not bored to death.

purport: 聲稱
involuntary: 不知不覺(jué)的
respiratory reflex: 呼吸反射
inhalation: 吸入
exhalation: 呼出
spinal: 脊椎的
cardiovascular system: 心血管系統(tǒng)
falls short of: 不足以,達(dá)不到
at a loss: 困惑的
brainstem: 腦干
sclerosis: 硬化癥
fetus: 胎兒
womb: 子宮

(來(lái)源:coolquiz.com 英語(yǔ)點(diǎn)津 Annabel 編輯)

我想了解更多趣味百科知識(shí)

 
 
相關(guān)文章 Related Stories
 
美元的符號(hào)$是怎么來(lái)的 打哈欠真的會(huì)傳染嗎?(通訊員稿) 打嗝是怎么回事
你被健忘癥困擾嗎 拉鏈?zhǔn)钦l(shuí)發(fā)明的 凡士林是怎么來(lái)的
         
 
 
 
 
 
         
 
 

48小時(shí)內(nèi)最熱門

     
  女孩的心思誰(shuí)能猜:Suspended from class
  各種各樣的“錢”
  “搶鏡頭”怎么說(shuō)
  姚明婚后打算:備戰(zhàn)奧運(yùn)第一

本頻道最新推薦

     
  為什么畢業(yè)時(shí)要穿學(xué)位服
  We cats can use chopsticks, too!
  不受歡迎的夜半歌聲:打鼾
  US Independence Day(美國(guó)國(guó)慶日)
  Exercise after dinner

論壇熱貼

     
  “低生育,素質(zhì)好,男女都是寶”,怎么譯為好?請(qǐng)教高手!
  請(qǐng)問(wèn)“老鄉(xiāng)”這個(gè)詞怎么翻譯?
  C-E: how to say "路盲"?
  各位,“相親”英語(yǔ)怎么說(shuō)?
  指紋上的ridges and loops是什么意思?
  請(qǐng)教一下 餃子的“餡” 用English怎么說(shuō)啊






主站蜘蛛池模板: 常熟市| 大庆市| 霍城县| 名山县| 高淳县| 桃园县| 普洱| 城固县| 武邑县| 苏尼特右旗| 乌恰县| 布拖县| 运城市| 蓬溪县| 舒城县| 牙克石市| 荔波县| 五河县| 黄冈市| 翁牛特旗| 界首市| 米脂县| 全椒县| 增城市| 藁城市| 金坛市| 尚志市| 分宜县| 阳山县| 增城市| 上高县| 新巴尔虎右旗| 仲巴县| 牙克石市| 辽宁省| 尉犁县| 南岸区| 垦利县| 福建省| 博客| 宣威市|