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

托福听力短文 II-10-1

时间:2009-01-13 00:50来源:互联网 提供网友:lanmengxue98   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)
(WA) Did you ever wonder why it is that most people are "programmed" to sleep at night instead of during the day? If there's something about the cycle of light and dark that's telling us when to sleep, then shouldn't the sleep cycle of a blind person be different? As it turns out, many blind people --- people with no visual perception1 of light at all --- do have the same sleep cycle as sighted people.

So now you're wondering, "How can this happen?" The answer is: hormones3 --- one hormone2 in particular. It's called melatonin. In sighted people, the level of melatonin goes up at night (or when it's dark) and goes down in the day (or when it's light). It's believed that it's the presence of this hormone in the blood that gives us the urge to sleep. If an increase in melatonin level "programs" sighted people to sleep at night, then what about blind people?

A researcher named Dr. Charles Czeisler, tells about an interesting experiment. He tried shining a bright light into the eyes of some blind people. When he did this, he noticed that the level of the melatonin in the blood of these subjects went down --- just as it would do for sighted people. Somehow, the eyes of these subjects, even though they were damaged and had no visual perception of light, could tell their brain when there was more or less light. Now, this doesn't work for all blind people; in fact, most of Czeisler's subjects had no hormonal4 response to light at all. Further research may be able to explain this sensitivity5 to light in terms of the type of blindness of the subject.

点击收听单词发音收听单词发音  

1 perception BM6xj     
n.感知,感觉,觉察(力);认识,观念,看法
参考例句:
  • What's your perception of the matter?你对此事有什么看法?
  • He was a man of keen perception.他是一个感觉敏锐的人。
2 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。
3 hormones hormones     
n. 荷尔蒙,激素 名词hormone的复数形式
参考例句:
  • 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。
  • The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。
4 hormonal Fcpx6     
adj.激素的
参考例句:
  • Some viral diseases are more severe during pregnancy, probably tecause of hormonal changes. 有些病毒病在妊娠期间比较严重,可能是由于激素变化引起的。
  • She underwent surgical intervention and a subsequent short period of hormonal therapy. 他接受外科手术及随后短暂荷尔蒙治疗。
5 sensitivity 4DtzQ     
n.敏感(性),灵敏(度)
参考例句:
  • Hearing sensitivity declines with age.听觉因年老而衰退。
  • Such is the sensitivity of the information that only two people are allowed to know it.这信息极为敏感,只允许两个人知道。
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:   托福听力  托福短文
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