在线观看亚洲精品专区-在线观看亚洲免费-在线观看亚洲免费视频-在线观看亚洲欧美-欧美freexxx-欧美free嫩交video

食品伙伴網服務號
 
 
當前位置: 首頁 » 專業英語 » 英語短文 » 正文

我們為什么打哈欠

放大字體  縮小字體 發布日期:2008-05-14
核心提示:打哈欠是一個人人都會、一旦啟動就無法中途停止的動作。幾乎所有動物都會打哈欠。貓咪睡前睡后哈欠連連,一副自我感覺良好的樣子;大大小小的猩猩都會打哈欠,有的還會用手蓋住嘴巴,以免被別的猩猩誤解為侵略行為。母親肚子里的胎兒也會打哈欠.那么,哈欠究竟是怎么回


    打哈欠是一個人人都會、一旦啟動就無法中途停止的動作。幾乎所有動物都會打哈欠。貓咪睡前睡后哈欠連連,一副自我感覺良好的樣子;大大小小的猩猩都會打哈欠,有的還會用手蓋住嘴巴,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: 不知不覺的
    respiratory reflex: 呼吸反射
    inhalation: 吸入
    exhalation: 呼出
    spinal: 脊椎的
    cardiovascular system: 心血管系統
    falls short of: 不足以,達不到
    at a loss: 困惑的
    brainstem: 腦干
    sclerosis: 硬化癥
    fetus: 胎兒
    womb: 子宮

 

更多翻譯詳細信息請點擊:http://www.trans1.cn
 
關鍵詞: 打哈欠
[ 網刊訂閱 ]  [ 專業英語搜索 ]  [ ]  [ 告訴好友 ]  [ 打印本文 ]  [ 關閉窗口 ] [ 返回頂部 ]
分享:

 

 
推薦圖文
推薦專業英語
點擊排行
 
 
Processed in 7.602 second(s), 1273 queries, Memory 6.86 M
主站蜘蛛池模板: 永久精品免费影院在线观看网站 | 国产高清色播视频免费看 | 奇米7777 | 五月天丁香激情 | h在线免费 | 天堂8资源8在线 | 免费啪视频观在线视频在线 | 日本不卡高清视频 | 床上激情四射 | 2019偷偷狠狠的日日 | 国产精品7m凸凹视频分类大全 | 清冷双性被cao的合不拢腿 | 在线观看免费国产 | 亚洲高清视频一区 | 天天操天天摸天天碰 | 毛片又大又粗又长又硬 | 欧美精品福利 | 国产盗摄女厕美女嘘嘘 | 国内精品久久久久影院男同志 | 亚洲精品视频在线 | 国产精品午夜在线观看 | 5g国产精品影院天天5g天天爽 | 日本a级片在线观看 | 中文字幕在线观看一区 | 久久综合性| 操黄色| 日本www高清 | 国产一级特黄高清免费大片 | 久久精品re| 久久久噜噜噜久久久午夜 | 亚洲国产精品久久久久婷婷老年 | 午夜免费观看_视频在线观看 | 欧美乱理伦另类视频 | 97久久人人| 又色又爽视频 | 经典三级一区二区三区视频 | 天天干天天在线 | 成年ssswww日本 | 你懂得网址在线观看 | 黄色www| h在线免费视频 |