1. VOA英语学习网
  2. 设首页|英语四级|英语六级|英语日记|英文自我介绍|英语话剧剧本
  3. 打包下载 | VOA打包 | BBC打包 | 日语 韩语
  4. 手机版
  1. 英语学习网站推荐
  2. 剑桥英语考试认证
  3. 外教口语面对面课程

BBC英语六分钟 第200期:边缘地带的生命

发表时间:2017-08-28内容来源:VOA英语学习网
This is a download from BBC Learning English. To find out more, visit our website. 6 Minute English from BBC Learning English. com. 本文来自BBC Learning English。如需获得更多内容请访问我们的网站。BBC Learning English. com 英语六分钟节目。 Alice: Hello and welcome to 6 Minute English. I'm Alice… 大家好,欢迎收听英语六分钟,我是爱丽丝。 Neil: And I'm Neil. So Alice, what's your ideal place to be? 我是尼尔。爱丽丝,你理想的生活环境是什么样子的? Alice: Curled up on the sofa with a good book in front of a log fire. Last night it was very cold. 在壁炉前,拿一本书缩在沙发里。昨晚太冷了。 Neil: Well, for me, lying in a hammock under a palm tree on a tropical beach with a cool breeze. I don't like when it's too hot. 我想在热带沙滩的棕榈树下,躺在吊床里,享受着阵阵微风。我不喜欢太热的天气。 Alice: Yes, true. Humans don't cope well with extremes of temperature but some species do. The subject of today's show is extremophiles– these are microorganisms that have adapted to live in what we would consider to be extreme conditions. For example, living in near boiling acidic water or frozen at the bottom of an Antarctic lake. 没错,人类不能适应极端温度,但有些物种却可以。今天节目的主题是极端微生物——可以适应极端环境的微生物。例如,在滚烫的酸性水中或在南极湖底的冰层下存活的微生物。 Neil: Those do sound like pretty extreme conditions. 这些都是很极端的环境。 Alice: Yes. The thing is, what sounds hostile – or unfriendly – to us, are perfect environments for extremophiles and in fact they wouldn't survive without them. Now, are you tough enough to face up to today's quiz question, Neil? 没错,对我们不利的环境却非常适合极端微生物生活。事实上如果没有这种环境,它们将无法存活。你能坚强地面对今天的问题吗? Neil: I think so. 没问题。 Alice: Alright then, here goes: which US National Park is home to geysers – or hot springs that shoot hot water and steam into the air– which have extremophiles living in them? Is it…a) Grand Canyon? b) Death Valley National Park? Or c) Yellowstone? 好的,问题是:美国哪个国家公园有间歇泉——能喷发热水和水蒸气的温泉——其中有极端微生物存活?a) 大峡谷?b) 死亡谷国家公园?还是c) 黄石公园? Neil: That's easy - it has to be c) Yellowstone. 很简单,一定是c) 黄石公园。 Alice: OK, well we'll find out if you got the answer right later on in the show. But, moving on, now, Neil, did you know that extremophiles belong to an entirely different group of living things to other animals and plants? 好的,稍后,我们再看你的回答是否正确。现在我们继续。尼尔,你知道吗,极端微生物是完全不同于其他动植物的生物群。 Neil: No. I imagined extremophiles would be like insects, because insects are pretty tough, aren't they? 不知道。我以为极端微生物和昆虫一样,因为昆虫有着顽强的生命力,不是吗? Alice: Yes, that's true. But remember, extremophiles are microorganisms – they're really tiny. Let's listen to Ian Crawford, Professor of Planetary Science and Astrobiology at Birkbeck University of London. He tells us how in the 1970s a scientist called Carl Woese identified a new kingdom of living things that he called archaea– meaning ancient ones. The extremophiles belong to this group. 这没错。但你要知道,极端微生物属于微生物,他们非常小。我们来听听伦敦大学伯贝克学院行星科学和天体生物学教授伊恩·克劳福德的看法。他讲述的是:在20世纪70年代,一位名叫卡尔·乌斯的科学家是如何发现古生菌这一新生物王国的,archaea是指古代的生物。极端微生物就属于这个群体。 Well, the old tree of life idea basically talked about empires if you like, of plants, and animals, and things that we can see, essentially. We put a great deal of emphasis on large organisms and the traditional distinction in biology between botany and zoology. What it really did was say that's all wrong– there's really only three major groups in life: there's the archaea, the bacteria, and the eukaryotes, which is all of this complex life; and so it kind of put humans into a small corner of the tree of life next to plants and whatever else. It kind of squashes us again after being the centre of the universe. 古老的生命之树主要说的是植物、动物以及我们所能看到的事物王国。我们着重强调大型生物体,以及生物学上植物学与动物学之间的传统区别。古生菌的存在说明之前的观点是错误的——生命有三大类:古生菌、细菌和真核生物,复杂生命体都属于真核生物。所以人类仅是生命树的一小个小分支,与植物等并列。这让自以为是宇宙中心的我们再次受挫。 Neil: So botany is the study of plant life, and zoology is the study of animal life. But maybe you can explain archaea, and eukaryotes, Alice. botany是研究植物的学科,zoology是研究动物的学科。也许你应该解释一下古生菌和真核生物。 Alice: Archaea are a group of single-celled microbes similar to bacteria but different to all other known types. Eukaryote is the scientific term for organisms with a much larger and more complex type of cell– and this group includes all animals, plants, and fungi. 古生菌是指单细胞微生物,类似于细菌,但是不同于已知的细菌类型。真核生物是指具有更大更复杂细胞的生物体,真核生物包括所有的动物、植物和真菌。 Neil: But why are archaea so important? Why do they need a whole biological domain to themselves, while we humans get squashed up in one domain with plants and fungi? 为什么古生菌如此重要?为什么它们能单独成为一个分类?然而我们人类要和植物、真菌挤在一个分类里? Alice: Well, Neil, it's likely they've have been living on our planet ever since the Earth became habitable– and that's billions of years. And they are still living and thriving in a whole range of different environments today. 尼尔,似乎自地球成为宜居的星球起,它们就已经存在了——已经有几十亿年的光景了。如今它们依旧在不同的环境中欣欣向荣。 Neil: And when something is thriving it means it's doing well! So tell us about where they live, Alice. thriving是指某物生活的很好。爱丽丝,你来告诉我们古生菌在哪里存活吧。 Alice: Some live in hydrothermal vents – holes in the ocean floor hundreds of metres down where there's lots of pressure and no sunlight. And mineral-rich superheated water is coming out of the Earth's crust and then flowing out through these holes. 一些存活于热液喷口——据海平面千米以下的洞口,那里压力很大,没有光照。地壳里富含矿物质的过热水从这些洞口流出。 Neil: I see… Well, what about cold-loving extremophiles? 我明白了。那喜欢寒冷环境的极端微生物呢? Alice: Well, scientists have found them in hidden lakes trapped beneath ice sheets hundreds of metres thick in Antarctica. It takes days to drill through the ice to reach the water. 在隐藏于南极的湖泊中,科学家发现极端微生物存在于上千米厚的冰层下。他们要花费好几天才能把冰打穿,够到湖水。 Neil: And how do they survive down there? 他们怎么存活呢? Alice: Well, these microbes have found a way of getting energy from certain minerals like iron and sulphur present in the water. 这些微生物通过吸收水中的一些矿物质来获取能量,如铁和硫磺。 Neil: That sounds clever for a microbe – how did they figure that out? 这些微生物还很聪明,他们是怎样做到的呢? Alice: It isn't a question of cleverness - it's a question of adaptation. Extremophiles are extremely well adapted to their environment and they appeared on Earth much earlier than more complex life forms. Let's hear from Nick Lane, Reader in Evolutionary Biochemistry at University College London. 这与聪明无关,而与他们的适应能力有关。极端微生物能够极好地适应环境,他们比复杂的生命体更早地出现在地球上。我们来听听伦敦大学学院进化生物化学教授尼克.连恩的看法。 The origin of the Eukaryotic cell, it seems to have happened once, it took about 2 billion years before that happened. Then there was kind of a great leap forward at the cellular level, but another billion years went by before we see animals. 真核生物的出现耗费了近20亿年的时间,而且仅出现了一次。之后,细胞快速发展,但是几十亿年之后,我们才看到了动物。 Neil: So, basically, the animal kingdom is much newer than the archaean kingdom. 所以,动物比古生菌出现的晚。 Alice: Indeed. And now it's time for the answer to today's quiz question, Neil. I asked: which US National Park is home to geysers that have extremophiles living in them? Is it… a) Grand Canyon, b) Death Valley National Park or c) Yellowstone? 没错,是时候公布今天问题的答案了。我问你:美国哪一个国家公园有间歇泉,其中生存着极端微生物?a) 大峡谷, b) 死亡谷国家公园,还是 c) 黄石公园? Neil: And I said c) Yellowstone. I must be right. 我选的是黄石公园,我肯定答对了。 Alice: Yes, Neil, you are right - it's Yellowstone National Park. Every year, scientists discover remarkable new microbes in Yellowstone's hot springs, with implications for medicine, agriculture and energy, as well as offering clues to the formation of the earliest life on Earth. 没错,尼尔,你答对了。是黄石国家公园。每年,科学家们都在黄石的温泉中发现新的微生物,这对医药、农业和能源有着重大影响。这些微生物还提供了与地球上最早生命的形成有关的线索。 Neil: Very interesting. Now, here are the words we heard today: 很有意思。现在我们来听听今天学到的单词。 extremophiles 极端微生物 hostile 敌对的,不友好的 geysers 间歇泉 microorganisms 微生物 botany 植物学 zoology 动物学 archaea 古生菌 eukaryote 真核生物,真核细胞 thriving 繁盛的,欣欣向荣的 hydrothermal vents 热液喷口 Alice: And that's the end of today's 6 Minute English. Don't forget to join us again soon! 今天的英语六分钟就到这里了。下期再会! Both: Bye! 再见! 6 Minute English from the BBC. BBC英语六分钟。 来自:VOA英语网 文章地址: http://www.tingvoa.com/html/20170828/488819.html
VOA,VOA慢速英语,英语学习网,英语新闻,学习方法