TED演讲：细菌是怎样交流的(5)_在线英语听力室

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　　But then if you think about it, the squid has this terrible problem 但是如果你再深入地想一下，这乌贼会有一个可怕的问题，

　　because it's got this dying, thick culture of bacteria and it can't sustain that. 因为在它的体内，这些黏稠的细菌会不断的增长，死亡，乌贼无法维持这些细菌的生长。

　　And so what happens is every morning when the sun comes up the squid goes back to sleep, it buries itself in the sand, 因此每天早上当太阳升起后，它将自己埋藏在沙中，进入睡眠，

　　and it's got a pump that's attached to its circadian rhythm, 而且它有一个与日夜周期同步的活泵，

　　and when the sun comes up it pumps out like 95 percent of the bacteria. 当太阳升起时，它将大约95%的细菌排出体外。

　　Now the bacteria are dilute¹, that little hormone² molecule³ is gone, so they're not making light -- but of course the squid doesn't care. 既然细菌被稀释了，这些小荷尔蒙分子也随之消失，因此它们不发光了，但乌贼当然不在意。

　　It's asleep in the sand. And as the day goes by the bacteria double, 它正在沙中睡觉呢。当一天过去，这些细菌持续分裂生长，

　　they release the molecule, and then light comes on at night, exactly when the squid wants it. 它们释放出这些分子，然后又开始在晚上发光，刚好就是乌贼需要光线的时候。

　　And so first we figured out how this bacterium⁴ does this, 我们先了解这些细菌为什么会有这种现象，

　　but then we brought the tools of molecular⁵ biology to this to figure out really what's the mechanism⁶. 然后我们使用分子生物学的方法来研究真正的分子机制是什么。

　　And what we found -- so this is now supposed to be, again, my bacterial⁷ cell 我们发现了--再一次，想象这是我的细菌

　　is that Vibrio fischeri has a protein -- that's the red box -- it's an enzyme⁸ that makes that little hormone molecule, the red triangle. 费氏弧菌有一种蛋白质，这个红色的方块--它是制造这小荷尔蒙分子的酵素。

　　And then as the cells grow, they're all releasing that molecule into the environment, so there's lots of molecule there. 当细胞生长时，他们全都释放这个分子到环境中，因此环境里有一堆这种分子。

　　And the bacteria also have a receptor on their cell surface that fits like a lock and key with that molecule. 这些细菌的细胞表面，同时还有一种受器，与此分子的构造就如同钥匙与锁一般的吻合。

　　These are just like the receptors on the surfaces of your cells. 它们就如同你身体细胞表面上的受器一般。

　　And when the molecule increases to a certain amount -- which says something about the number of cells 当这些分子增加到一定的量时--也意味着这些细胞数量的增加，

　　it locks down into that receptor and information comes into the cells that tells the cells to turn on this collective behavior of making light. 荷尔蒙与受器相结合，讯息开始向细胞内部传递，这个讯息告诉这些细胞开始表现此集体行为，并开始发光。

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收听单词发音

1 dilute
vt.稀释，冲淡；adj.稀释的，冲淡的
参考例句：
The water will dilute the wine.水能使酒变淡。 Zinc displaces the hydrogen of dilute acids.锌置换了稀酸中的氢。

2 hormone
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 molecule
n.分子，克分子
参考例句：
A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。 This gives us the structural formula of the molecule.这种方式给出了分子的结构式。

4 bacterium
n.(pl.)bacteria 细菌
参考例句：
The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。 A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

5 molecular
adj.分子的；克分子的
参考例句：
The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。 For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

6 mechanism
n.机械装置；机构，结构
参考例句：
The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。 The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

7 bacterial
a.细菌的
参考例句：
Bacterial reproduction is accelerated in weightless space. 在失重的空间，细菌繁殖加快了。 Brain lesions can be caused by bacterial infections. 大脑损伤可能由细菌感染引起。

8 enzyme
n.酵素，酶
参考例句：
Above a certain temperature,the enzyme molecule will become unfolded.超过一定温度，酶分子将会展开。 An enzyme that dissolves the fibrin of blood clots.能溶解血凝块中的纤维的酶。

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TED演讲：细菌是怎样交流的(5)