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托福阅读背景之深海生物的生存

时间：2014-03-30 08:33:05

（单词翻译:单击）

 　　Once it seemed that the ocean floor was a desert of darkness. As everyone knew， sunlight was what made life possible by fueling photosynthesis1， and sunlight can penetrate2 only the first few hundred yards of the ocean’s great depths. Lower， a few creatures might still eke3 out a living by scrounging the organic detritus4 that drifts down from the surface of the sea. But thousands of feet down， in the utter blackness at the ocean’s bottom， there could be practically nothing.

　　Then， in 1977， underwater explorers discovered that there was in fact something， and quite a lot of it. At mid-ocean ridges5， where new ocean floor rises up as molten rock from Earth’s interior， where cold seawater mixes with the rising magma and， heated to 650 degrees， spews back up through chimney-shaped hydrothermal vents6， researchers stumbled across bustling7 ecosystems8. Clinging to the sides of the chimneys were thick white mats of bacteria; around them were eight-foot-long stalk-shaped worms， rocking in the water， while eyeless shrimp9 seethed10 around the chimneys like maggots. All were thriving on the energy bound up in the vents’ sulfur11 compounds. The seafloor might still be dark， but now it was known to be dotted with gardens.
　　In just the past eight years， however， underwater explorers have discovered that this picture is still incomplete： there is light at the bottom of the sea. Hydrothermal vents glow， and while the light is too faint to be perceived by the human eye， that hardly means it is without significance. Physicists12 maintain that although some of the light may be created by the intense heat， much of it must be attributed to some as-yet- unknown process. Biologists， meanwhile， say there is sufficient light at these vents for photosynthesis to take place. Researchers can’t say yet whether any creatures are actually living off this light， but if they are， they will represent the first known instance of natural photosynthesis without sunlight. The evolutionary13 implications may run deeper： it’s possible not only that this deep light is fueling photosynthesis now， but that， 3.8 billion years ago， it got the whole process started.
　　本篇关键词：
　　Photosynthesis
　　thousands of feet down
　　ocean’s bottom
　　mid-ocean ridges
　　650 degrees
　　bustling ecosystems
　　bound up in
　　sulfur compounds
　　light at the bottom of the sea
　　photosynthesis without sunlight
　　中文相关知识：
　　无处不在的细菌：没有阳光就不能进行光合作用，地面生物就无法生存了。但是在2000—3000米深的海底，没有阳光的地方，各种生物又是以什么为食物来维持生命呢?科学家从海底采取的水样中发现了奥妙。原来在水下2500到3000米的海底常有温泉出现，这些温泉喷涌出高达350摄氏度的水流。海底热泉水从地下带上来许多硫酸盐，硫酸盐在高温高压下变成了有臭鸡蛋味的硫化氢，一些以硫化氢为营养的细菌以极快的速度繁衍。细菌通过摄取温泉里丰富的化合物获得能量，它们帮助温泉水把周围变成一片生机勃勃的海底绿洲。小动物就以细菌为食，大动物又以小动物为食，这样就形成了新的食物链。
 

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1 photosynthesis A2Czp     
n.光合作用
参考例句：
  • In apple trees photosynthesis occurs almost exclusively in the leaves.苹果树的光合作用几乎只发生在叶内。
  • Chloroplasts are the structures in which photosynthesis happens.叶绿体就是光合作用发生的地方。
2 penetrate juSyv     
v.透(渗)入；刺入，刺穿；洞察，了解
参考例句：
  • Western ideas penetrate slowly through the East.西方观念逐渐传入东方。
  • The sunshine could not penetrate where the trees were thickest.阳光不能透入树木最浓密的地方。
3 eke Dj6zr     
v.勉强度日，节约使用
参考例句：
  • They had to eke out a livinga tiny income.他们不得不靠微薄收入勉强度日。
  • We must try to eke out our water supply.我们必须尽量节约用水。
4 detritus J9dyA     
n.碎石
参考例句：
  • Detritus usually consists of gravel, sand and clay.岩屑通常是由砂砾，沙和粘土组成的。
  • A channel is no sooner cut than it chokes in its own detritus.一个河道刚被切割了不久，很快又被它自己的碎屑物质所充塞。
5 ridges 9198b24606843d31204907681f48436b     
n.脊( ridge的名词复数 )；山脊；脊状突起；大气层的)高压脊
参考例句：
  • The path winds along mountain ridges. 峰回路转。
  • Perhaps that was the deepest truth in Ridges's nature. 在里奇斯的思想上，这大概可以算是天经地义第一条了。
6 vents 3fd48768f3da3e458d6b73926735d618     
（气体、液体等进出的）孔、口( vent的名词复数 )； （鸟、鱼、爬行动物或小哺乳动物的）肛门； 大衣等的)衩口； 开衩
参考例句：
  • He always vents his anger on the dog. 他总是拿狗出气。
  • The Dandelion Patch is the least developed of the four active vents. “蒲公英区”在这四个活裂口中是发育最差的一个。
7 bustling LxgzEl     
adj.喧闹的
参考例句：
  • The market was bustling with life. 市场上生机勃勃。
  • This district is getting more and more prosperous and bustling. 这一带越来越繁华了。
8 ecosystems 94cb0e40a815bea1157ac8aab9a5380d     
n.生态系统( ecosystem的名词复数 )
参考例句：
  • There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
  • Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样，从雨林到半荒漠等不一而足。 来自辞典例句
9 shrimp krFyz     
n.虾，小虾；矮小的人
参考例句：
  • When the shrimp farm is built it will block the stream.一旦养虾场建起来，将会截断这条河流。
  • When it comes to seafood,I like shrimp the best.说到海鲜，我最喜欢虾。
10 seethed 9421e7f0215c1a9ead7d20695b8a9883     
（液体）沸腾( seethe的过去式和过去分词 )； 激动，大怒； 强压怒火； 生闷气(~with sth|~ at sth)
参考例句：
  • She seethed silently in the corner. 她在角落里默默地生闷气。
  • He seethed with rage as the train left without him. 他误了火车，怒火中烧。
11 sulfur ps4wC     
n.硫，硫磺（=sulphur）
参考例句：
  • Sulfur emissions from steel mills become acid rain.炼钢厂排放出的硫形成了酸雨。
  • Burning may produce sulfur oxides.燃烧可能会产生硫氧化物。
12 physicists 18316b43c980524885c1a898ed1528b1     
物理学家( physicist的名词复数 )
参考例句：
  • For many particle physicists, however, it was a year of frustration. 对于许多粒子物理学家来说，这是受挫折的一年。 来自英汉非文学 - 科技
  • Physicists seek rules or patterns to provide a framework. 物理学家寻求用法则或图式来构成一个框架。
13 evolutionary Ctqz7m     
adj.进化的；演化的，演变的；[生]进化论的
参考例句：
  • Life has its own evolutionary process.生命有其自身的进化过程。
  • These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。