轻松背单词新浪微博 轻松背单词腾讯微博
轻松背单词微信服务号
当前位置:首页 -> 12级英语阅读 - > 基因技术能否使人更聪明
基因技术能否使人更聪明
添加时间:2014-06-30 15:48:30 浏览次数: 作者:未知
Tip:点击数字可快速查看单词解释  
  • Many people dream of having a smarter brain. Princeton neurobiologist Joseph Z. Tsien found the key. In September he announced that he’d built a better mouse by altering a gene1 that affects learning and memory. A similar process of gene manipulation might conceivably be used one day to boost intelligence in humans.

    The secret lies in a feature of brain cells called the nmda receptor, which Tsien likens to a cylindrical2 tube or window that mediates3 the flow of information. When the window is open, chemicals called neurotransmitters flow through easily and memory is registered and stored. But as organisms mature, the window begins to close. (This may explain why children lose their facility for learning new languages when they reach sexual maturity4 and why some people suffer memory loss as they age.)

    Tsien noticed that the receptor worked more efficiently5 when teamed with the gene NR2B, so he introduced extra NR2B genes6 into a batch7 of fertilized8 mouse eggs. In a normal mouse, the memory window is open for just 150-thousandths of a second. In Tsien’s specially9 engineered mice, the window opens for 250-thousandths of a second, long enough to make a remarkable10 difference in memory retention11. When he pitted his mice against common mice, they won paws down. Ordinary mice could recognize a Lego block for 12 hours, but smart mice could remember the block for up to three days. "That’s a profound enhancement," Tsien says.

    Can it be done with humans? Maybe, but genetic12 engineering will have to make some extraordinary advances first. And some thorny13 ethical14 issues will have to be resolved. Meanwhile, Tsien promises to keep his furry15 little geniuses locked up in a lab, far from your larder16. "Otherwise," he says, "you might need a smart cat or a smart mousetrap to catch them."

    许多人都希望自己能变成更聪明。普林斯顿神经生物学家Joseph Z. Tsien就找到了这把开启智慧之门的钥匙:他于九月宣布,通过改变影响学习和记忆能力的基因培养出了一只聪明的老鼠。类似的基因处理技术有望在未来日子里运用到人脑,以推动人类智慧的飞跃。

    该技术的奥秘就在于名为nmda感受器的脑细胞的功能。Tsien将其比作一个传递信息流的圆柱通道或窗口。当窗口开放时,某种称为神经传递素的化学物质就能轻易流过,记忆因此登记并存储了下来。然而,当器官成熟时,这扇窗口就开始关闭。(这也能解释为何儿童长大后(性器官成熟之时)会失去掌握新语言的能力,以及为何某些人年老时会患失忆)。

    Tsien注意到,当感受器与名为NR2B的基因协作时效率会更高。因此,他将NR2B基因植入一批老鼠的受精卵中。一只普通老鼠的记忆之窗仅开放千分之150秒。而经Tsien植入基因的老鼠,记忆之窗能开放千分之250秒,这已经能够使其记忆力发生惊人的改变。当他让自己的老鼠与普通老鼠互斗时,它们竟能轻而易举地取胜。普通老鼠能够保留关于Lego block的记忆12小时,而聪明的老鼠居然能将记忆保持三天。“这可是一个意义深远的进步。”Tsien这样说。

    那么,人类也能接受这种基因移植吗? 或许可以,但前提是基因工程得首先做出非凡的成就,还必须解决一系列棘手的伦理问题。Tsien保证他一定会将那些披着毛皮的小天才锁入实验室,远离人们的食品柜。“否则,”他说,“为了捉住他们,人们就不得不去寻找更聪明的猫或者功能更强的捕鼠器了。”

     12级    英文科普 


    点击收听单词发音收听单词发音  

    1 gene [dʒi:n] WgKxx   第7级
    n.遗传因子,基因
    参考例句:
    • A single gene may have many effects. 单一基因可能具有很多种效应。
    • The targeting of gene therapy has been paid close attention. 基因治疗的靶向性得到了密切关注。
    2 cylindrical [si'lindrikəl] CnMza   第7级
    adj.圆筒形的
    参考例句:
    • huge cylindrical gas tanks 巨大的圆柱形贮气罐
    • Beer cans are cylindrical. 啤酒罐子是圆筒形的。
    3 mediates [ˈmi:dieits] 9cf5b4b4c1ee4c1361a2114028f23c30   第9级
    调停,调解,斡旋( mediate的第三人称单数 ); 居间促成; 影响…的发生; 使…可能发生
    参考例句:
    • We therefore investigated whether hypercoagulability mediates a beneficial effect during denovo atherogenesis. 因此我们研究了高凝在原位动脉粥样硬化形成中是否介导了有益的作用。
    • Not happy when the mood that how mediates oneself? 不开心的时候怎样调解自己的情绪?
    4 maturity [məˈtʃʊərəti] 47nzh   第7级
    n.成熟;完成;(支票、债券等)到期
    参考例句:
    • These plants ought to reach maturity after five years. 这些植物五年后就该长成了。
    • This is the period at which the body attains maturity. 这是身体发育成熟的时期。
    5 efficiently [ɪ'fɪʃntlɪ] ZuTzXQ   第8级
    adv.高效率地,有能力地
    参考例句:
    • The worker oils the machine to operate it more efficiently. 工人给机器上油以使机器运转更有效。
    • Local authorities have to learn to allocate resources efficiently. 地方政府必须学会有效地分配资源。
    6 genes [dʒi:nz] 01914f8eac35d7e14afa065217edd8c0   第7级
    n.基因( gene的名词复数 )
    参考例句:
    • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
    • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
    7 batch [bætʃ] HQgyz   第7级
    n.一批(组,群);一批生产量
    参考例句:
    • The first batch of cakes was burnt. 第一炉蛋糕烤焦了。
    • I have a batch of letters to answer. 我有一批信要回复。
    8 Fertilized ['fɜ:rtɪlaɪzd] 0f66e269f3e72fa001554304e59712da   第8级
    v.施肥( fertilize的过去式和过去分词 )
    参考例句:
    • The study of psychology has recently been widely cross-fertilized by new discoveries in genetics. 心理学研究最近从遗传学的新发现中受益匪浅。
    • Flowers are often fertilized by bees as they gather nectar. 花常在蜜蜂采蜜时受粉。
    9 specially [ˈspeʃəli] Hviwq   第7级
    adv.特定地;特殊地;明确地
    参考例句:
    • They are specially packaged so that they stack easily. 它们经过特别包装以便于堆放。
    • The machine was designed specially for demolishing old buildings. 这种机器是专为拆毁旧楼房而设计的。
    10 remarkable [rɪˈmɑ:kəbl] 8Vbx6   第7级
    adj.显著的,异常的,非凡的,值得注意的
    参考例句:
    • She has made remarkable headway in her writing skills. 她在写作技巧方面有了长足进步。
    • These cars are remarkable for the quietness of their engines. 这些汽车因发动机没有噪音而不同凡响。
    11 retention [rɪˈtenʃn] HBazK   第7级
    n.保留,保持,保持力,记忆力
    参考例句:
    • They advocate the retention of our nuclear power plants. 他们主张保留我们的核电厂。
    • His retention of energy at this hour is really surprising. 人们惊叹他在这个时候还能保持如此旺盛的精力。
    12 genetic [dʒəˈnetɪk] PgIxp   第7级
    adj.遗传的,遗传学的
    参考例句:
    • It's very difficult to treat genetic diseases. 遗传性疾病治疗起来很困难。
    • Each daughter cell can receive a full complement of the genetic information. 每个子细胞可以收到遗传信息的一个完全补偿物。
    13 thorny [ˈθɔ:ni] 5ICzQ   第11级
    adj.多刺的,棘手的
    参考例句:
    • The young captain is pondering over a thorny problem. 年轻的上尉正在思考一个棘手的问题。
    • The boys argued over the thorny points in the lesson. 孩子们辩论功课中的难点。
    14 ethical [ˈeθɪkl] diIz4   第8级
    adj.伦理的,道德的,合乎道德的
    参考例句:
    • It is necessary to get the youth to have a high ethical concept. 必须使青年具有高度的道德观念。
    • It was a debate which aroused fervent ethical arguments. 那是一场引发强烈的伦理道德争论的辩论。
    15 furry [ˈfɜ:ri] Rssz2D   第9级
    adj.毛皮的;似毛皮的;毛皮制的
    参考例句:
    • This furry material will make a warm coat for the winter. 这件毛皮料在冬天会是一件保暖的大衣。
    • Mugsy is a big furry brown dog, who wiggles when she is happy. 马格斯是一只棕色大长毛狗,当她高兴得时候她会摇尾巴。
    16 larder [ˈlɑ:də(r)] m9tzb   第12级
    n.食物贮藏室,食品橱
    参考例句:
    • Please put the food into the larder. 请将食物放进食物柜内。
    • They promised never to raid the larder again. 他们答应不再随便开食橱拿东西吃了。

    文章评论 共有评论 0查看全部

      会员登陆
      热门单词标签
    我的单词印象
    我的理解: