万物简史 第423期:生命的起源(17)

 　　Anniversaries were few and far between in the Archaean world. 在太古代的世界里，结婚周年纪念日是完全没有的。

　　For two billion years bacterial¹ organisms were the only forms of life. 在20亿年时间里，细菌是惟一的生命形式。

　　They lived, they reproduced, they swarmed², but they didn't show any particular inclination³ to move on to another, more challenging level of existence. 它们活着，它们繁殖，它们数量增加，但没有表现出想发展展到另一个更富挑战性的生存层面的特别倾向。

　　At some point in the first billion years of life, cyanobacteria, or blue-green algae⁴, 在生命的头10亿年的某个时候，藻青菌，或称蓝绿藻，

　　learned to tap into a freely available resource—the hydrogen that exists in spectacular abundance in water. 学会了利用大量存在的资源——存在于水中的特别丰富的氢。

　　They absorbed water molecules⁵, supped on the hydrogen, and released the oxygen as waste, and in so doing invented photosynthesis⁶. 它们吸叫水分子，吃掉了氢，排出了氧，在此过程中发明了光合作用。

　　As Margulis and Sagan note, photosynthesis is "undoubtedly⁷ the most important single metabolic⁸ innovation in the history of life on the planet" 正如马古利斯和萨根指出的，“光合作用无疑是本星球的生命史上所创造的最重要的新陈代谢方法”

　　and it was invented not by plants but by bacteria. 光合作用是由细菌而不是由植物发明的。

　　As cyanobacteria proliferated⁹ the world began to fill with O2 to the consternation¹⁰ of those organisms that found it poisonous—which in those days was all of them. 随着藻青菌的增多，世界开始充满氧气，发现氧是有毒的微生生深感吃惊——而在那个年代，那种微生物比比皆是。

　　In an anaerobic¹¹ (or a non-oxygen-using) world, oxygen is extremely poisonous. 在一个厌氧的（或不使用氧的）世界里，氧是剧毒的。

　　Our white cells actually use oxygen to kill invading bacteria. 我们的白血球实际上就是氧来杀死入侵的细菌。

　　That oxygen is fundamentally toxic¹² often comes as a surprise to those of us who find it so convivial¹³ to our well-being,  氧从根本上说是很毒的，我们听了往往会大吃一惊，因为许多人觉得呼吸氧是很舒服的事，

　　but that is only because we have evolved to exploit it. 但那只是因为我们已经逐步进化到了能利用氧。

　　To other things it is a terror. 对于别的东西来说，它是一种可怕的东西。

　　It is what turns butter rancid and makes iron rust¹⁴.  它使黄油变质，使铁生锈。

1 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。

2 swarmed   

密集( swarm的过去式和过去分词 )； 云集； 成群地移动； 蜜蜂或其他飞行昆虫成群地飞来飞去

参考例句：

• When the bell rang, the children swarmed out of the school. 铃声一响，孩子们蜂拥而出离开了学校。
• When the rain started the crowd swarmed back into the hotel. 雨一开始下，人群就蜂拥回了旅社。

3 inclination   

n.倾斜；点头；弯腰；斜坡；倾度；倾向；爱好

参考例句：

• She greeted us with a slight inclination of the head.她微微点头向我们致意。
• I did not feel the slightest inclination to hurry.我没有丝毫着急的意思。

4 algae   

n.水藻，海藻

参考例句：

• Most algae live in water.多数藻类生长在水中。
• Algae grow and spread quickly in the lake.湖中水藻滋蔓。

5 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

6 photosynthesis   

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。

7 undoubtedly   

adv.确实地，无疑地

参考例句：

• It is undoubtedly she who has said that.这话明明是她说的。
• He is undoubtedly the pride of China.毫无疑问他是中国的骄傲。

8 metabolic   

adj.新陈代谢的

参考例句：

• Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。
• A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。

9 proliferated   

激增( proliferate的过去式和过去分词 )； （迅速）繁殖； 增生； 扩散

参考例句：

• Books and articles on the subject have proliferated over the last year. 过去一年以来，论及这一问题的书和文章大量涌现。
• Influenza proliferated throughout the country. 流感在全国蔓延。

10 consternation   

n.大为吃惊，惊骇

参考例句：

• He was filled with consternation to hear that his friend was so ill.他听说朋友病得那么厉害，感到非常震惊。
• Sam stared at him in consternation.萨姆惊恐不安地注视着他。

11 anaerobic   

adj.厌氧的

参考例句：

• Anaerobic respiration occurs only in particularly active tissues such as muscles during severe exercise. 厌氧呼吸只有在处于剧烈运动状态的肌肉等特别活跃的组织中才会发生。
• Infection,especially anaerobic infection, is much more apt to occur.感染，特别是厌氧感染很容易发生。

12 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

13 convivial   

adj.狂欢的，欢乐的

参考例句：

• The atmosphere was quite convivial.气氛非常轻松愉快。
• I found it odd to imagine a nation of convivial diners surrendering their birthright.我发现很难想象让这样一个喜欢热热闹闹吃饭的民族放弃他们的习惯。

14 rust   

n.锈；v.生锈；(脑子)衰退

参考例句：

• She scraped the rust off the kitchen knife.她擦掉了菜刀上的锈。
• The rain will rust the iron roof.雨水会使铁皮屋顶生锈。