英语 英语 日语 日语 韩语 韩语 法语 法语 德语 德语 西班牙语 西班牙语 意大利语 意大利语 阿拉伯语 阿拉伯语 葡萄牙语 葡萄牙语 越南语 越南语 俄语 俄语 芬兰语 芬兰语 泰语 泰语 泰语 丹麦语 泰语 对外汉语

SSS 2010-03-18

时间:2010-05-20 06:02来源:互联网 提供网友:mark@li   字体: [ ]
特别声明:本栏目内容均从网络收集或者网友提供,供仅参考试用,我们无法保证内容完整和正确。如果资料损害了您的权益,请与站长联系,我们将及时删除并致以歉意。
    (单词翻译:双击或拖选)

Humans are pegged1 to a 24-hour cycle. We're locked into it not just by day and night—there’s the master timepiece in the brain called the circadian clock. But it doesn't make sense to live by a 24-hour clock in the Arctic, where it's dark or light for months at time. The solution? Lose the daily clock. Which is exactly what reindeer2 seem to have done, according to a study in Current Biology.                                           

 

Reindeer don't sleep eight hours like we do, and there's no obvious 24-hour pattern to their lives. They just chomp3 on tundra4, nap a few hours and feast again. But they still need to know when to mate, pack on fat or thicken their coats. So they probably rely on an annual clock instead, set by the hormone5 melatonin.

 

In humans melatonin levels rise at night, in response to darkness and cues from the circadian clock. In reindeer, even if they’re missing a circadian clock, melatonin levels still spike6 when it's dark and drop when it's light, making the equinoxes an ideal time to synchronize7 their annual clocks.

 

So ask a reindeer what time of year it is, and it may be able to give you the date. Just don't be offended if it won't give you the time of day.

 


点击收听单词发音收听单词发音  

1 pegged eb18fad4b804ac8ec6deaf528b06e18b     
v.用夹子或钉子固定( peg的过去式和过去分词 );使固定在某水平
参考例句:
  • They pegged their tent down. 他们钉好了账篷。 来自《简明英汉词典》
  • She pegged down the stairs. 她急忙下楼。 来自《现代英汉综合大词典》
2 reindeer WBfzw     
n.驯鹿
参考例句:
  • The herd of reindeer was being trailed by a pack of wolves.那群驯鹿被一只狼群寻踪追赶上来。
  • The life of the Reindeer men was a frontier life.驯鹿时代人的生活是一种边区生活。
3 chomp NrAzV     
v. (人、动物进食时)大声地咬,嚼得很响
参考例句:
  • I lost a tooth while chomping on a French baguette!我啃法棍面包时,崩掉了一颗牙!
  • They just chomp on tundra, nap a few hours and feast again.它们只是在苔原上大嚼特嚼,睡上几小时,接着再吃。
4 tundra dmtwW     
n.苔原,冻土地带
参考例句:
  • The arctic tundra is at the top of the world around the North Pole.北极冻原是指北极点周边的地区,是世界最高的地方。
  • There is a large amount of methane gas under the Siberian tundra.西伯利亚的冻土地带之下有大量的甲烷气体。
5 hormone uyky3     
n.荷尔蒙,激素,内分泌
参考例句:
  • Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
  • This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
6 spike lTNzO     
n.长钉,钉鞋;v.以大钉钉牢,使...失效
参考例句:
  • The spike pierced the receipts and held them in order.那个钉子穿过那些收据并使之按顺序排列。
  • They'll do anything to spike the guns of the opposition.他们会使出各种手段来挫败对手。
7 synchronize Lqlwy     
v.使同步 [=synchronise]
参考例句:
  • The sound on a film must synchronize with the action. 影片中的声音必须与动作配合一致。
  • You must synchronize your Inbox before selecting additional folders. 在选择其他文件夹前,您必须同步您的收件箱。
本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎点击提交分享给大家。
------分隔线----------------------------
TAG标签:   SSS  annual
顶一下
(0)
0%
踩一下
(0)
0%
最新评论 查看所有评论
发表评论 查看所有评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:
听力搜索
推荐频道
论坛新贴