大学生物专业英语6 (1)

1、2022-7-61Lesson sixThe origin and Diversity of Life生命的起源和多样性生命的起源和多样性2022-7-62vBig Bang big b大爆炸大爆炸vAn explosion producing a pressure oscillation of the order of a millibar or more at a distant point on the Earth. e.g., the eruption of Krakatoa in 1883. Large nuclear fusion explosions are comparable

2、.vexplosion iksplun 爆炸 vpressure oscillation ,slein压力波动, 冲击波 vof the order 大约 v millibar milib: 物毫巴 2022-7-63veruption irpn爆发vKrakatoa 喀拉喀托火山(印度尼西亚一火山岛) vnuclear fusion 核聚变,核融合vcomparable kmprbl可比较的,比得上的vbinomial system of nomenclature vbainumil nmn,kleit 双名法双名法vUses two Latin names, genus and speci

3、es, for each type of organism.vgenus di:ns (复genera denr ) 属, 2022-7-64vclade kleid 进化枝进化枝vIn a cladistic classification, organisms are placed into taxonomic groups called clades when they share characteristics that are thought to indicate common ancestry.vcladistic kldistik 进化枝的进化枝的 vclassification

4、 ,klsifikein分类分类, 分级分级 vtaxonomic tksnmik分类分类学的学的vancestry nsistri祖先祖先2022-7-65vclass 纲纲vA group used in the classification of living organisms. A class consists of a number of similar or closely related orders or occasionally of only one order. Classes are usually large and easily recognized groups

5、.vorder 目目 group 群体群体 vclosely related 关系相近的关系相近的2022-7-66vcoacervate kusveit团聚体，凝聚层团聚体，凝聚层vA collection of organic macromolecules surrounded by water molecules that are aligned to form a sphere.vcollection 集成集成, 聚积聚积 vmacromolecule ,mkrumlikju:l高分子高分子 valign 排列排列 vsphere sfi球体球体 2022-7-67vcontinent

6、al drift ,kntnentldrift 大陆漂大陆漂移移vThe theory that the present continents result from the break-up of a larger continent and have moved independently to their present positions.vresult from 由由.产生产生 break-up 分裂分裂 破碎破碎 vcore k:核心核心vThe core of the Earth is that part lying below the mantle.2022-7-68vmant

7、le mntl地幔地幔vcrust krst地壳地壳vThe crust of the Earth is the outer shell of the Earth, defined by its composition and the properties of some seismic waves.vcomposition 成分，合成物成分，合成物 vseismic waves saizmik震波震波2022-7-69vdivision divin门vA unit used in the classification of plants. A division consists of a n

8、umber of classes, or occasionally of only one class, with certain important characteristics in common.vcharacteristic ,kriktristik特性2022-7-610vfamily 科vA unit used in the classification of plants and animals. A family consists of a number of closely related or similar genera or occasionally of only

9、one genus. Family names end in-aceae or-ae in botany and in-ideae in zoology. vgeneradenr 属 genus di:ns vbotanybtni 植物学vzoology zldi:动物学, 生态2022-7-611vgenus di:ns属v(plural, genera) A unit used in the classification of plants and animals. A genus consists of a number of closely related species, and m

10、embers of the same genus often have a number of obvious characteristics in common by which they can clearly be seen to be related.vplural plurl复数的2022-7-612vkingdom kidm界vIn biology, a major category into which living material is classified.vcategory ktiri种类, 别, 范畴 vliving material 生活物质,活质vliposome

11、lipusum脂质体脂质体vA vesicle formed by the homogenization (emulsification) of phospholipids in dilute salt solutions. Liposomes are the prototypes of membrane-bound biologic structures.2022-7-613vvesicle vesikl小囊泡小囊泡 vhomogenization ,hmdnazein 均质化均质化vemulsification i,mlsifikein乳化乳化, 乳化作用乳化作用 vphospholipi

12、d ,fsfulipid磷脂磷脂 vdilute dailju:t冲淡冲淡, 稀释稀释 vsolution slu:n 溶液溶液vprototype pruttaip原型原型,典型典型vmembrane-bound 膜结合的膜结合的,膜约束的膜约束的2022-7-614vinterior intiri 内部内部core 核心核心vorder 目目vA unit used in the classification of plants and animals. An order consists of a number of similar or closely related families

13、 or only one family. Names of orders end typically in ales in plants and in -a in animals.vozone layer uzunlei 臭氧层臭氧层vA layer of the atmosphere, about 20-50 km above the surface, which contains ozone produced by ultraviolet radiation.2022-7-615vultraviolet radiation ,ltrvailit,reidiein紫外辐射vphylum fa

14、ilm 复复 phylafail 门门vA unit used in the classification of animals. A phylum consist of a number of classes, or occasionally of only one class, with certain important characteristics in common, implying that all members are descended from a common ancestor.vdescended from 从.下来 imply 暗示, 意味vancestor 祖先

15、, 祖宗 2022-7-616vproteinoid ,prutinid类蛋白(质)vA proteinlike structure of branched amino acid chains that is the basic structure of a microsphere. vbranched 分枝的 microsphere 微球体vspecies spi:i:z物种 种vA unit used in the classification of plants and animals. Ideally a species is defined as a group of organis

16、ms that interbreed with each other to produce fertile offspring.2022-7-617videally 理想地理想地 在观念上地在观念上地 vdefine 定义定义, 详细说明详细说明 group 群体群体vinterbreed ,intbri:d (使使)异种交配异种交配, (使使)混混种种vfertile f:tail能繁能繁殖的殖的vtaxon tksn (复复taxatks ) 分类单位，分类单位，分类群分类群vA unit of classification of any rank in the hierarchical

17、scale.vhierarchical ,hair:kikl 分等级的分等级的2022-7-618vscale 衡量衡量,测量测量,刻度刻度vtaxonomy tksnmi:分类学分类学vThe study of the theory, procedure, and rules of classification of organisms according to the similarities and differences between them.vprocedure 程序程序, 手续手续2022-7-6191.A home for life: Formation of the sol

18、ar system and planet earthv The story of lifes origins begins with the formation of the earth. v生命起源于地球的形成。生命起源于地球的形成。v The sequence of events that gave rise to our planet began, in turn, with the cosmic explosion physicists call the Big Bang. v 我们行星的形成开始于宇宙物理学家所命我们行星的形成开始于宇宙物理学家所命名的大爆炸。名的大爆炸。2022-7

19、-620v The sun at the center of our solar system condensed from a cloud of primordial matter roughly 5 billion years ago; the planets, including the earth, condensed about 4.6 billion years ago. v 太阳，位于太阳系中心，在大约太阳，位于太阳系中心，在大约5050亿年前，亿年前，由原始物质浓缩形成由原始物质浓缩形成; ; 行星行星, ,包括地球在内包括地球在内, , 生成于大约生成于大约4646亿年前。亿

20、年前。2022-7-621v The earth is composed of a number of layers: a solid crust, a semisolid mantle, and a largely molten (liquid) core that has a solid center.v v 地球由多层组成：坚硬的地壳，半流体的地幔地球由多层组成：坚硬的地壳，半流体的地幔和一个很大的熔解状态的和一个很大的熔解状态的(液体液体)地核地核, 地核有一地核有一个固体的中心。个固体的中心。2022-7-622v Basic physical features of Earth t

21、hat may have made the emergence of life possible include the planets size, temperature, composition, and distance from the sun. v 地球的基本物理特征地球的基本物理特征(使生命起源成使生命起源成为可能为可能)，包括行星的大小，温度，组成以，包括行星的大小，温度，组成以及离太阳的距离。及离太阳的距离。2022-7-623v The major current hypothesis holds that life arose spontaneously on the ea

22、rly earth by means of chemical evolution from nonliving substances.v 当前主要假设认为，在早期地球上当前主要假设认为，在早期地球上,生命生命自发的形成于非生命物质的化学进化。自发的形成于非生命物质的化学进化。2022-7-624v Evidence for prelife stages of chemical organization comes from laboratory experiments that try to duplicate the physical environment and chemical res

23、ources of the early earth. v 通过模拟早期地球的自然条件和化学资源，通过模拟早期地球的自然条件和化学资源，科学家在实验室中已经获得了化学有机体的生科学家在实验室中已经获得了化学有机体的生命前阶段的命前阶段的证据证据。（化学有机体的生命前阶段。（化学有机体的生命前阶段的的证据来源于实验室试验）证据来源于实验室试验）2. The emergence of life: organic and biological molecules on a primitive planet2022-7-625v These experiment, including the pione

24、ering work of Miller and Urey, have successfully produced organic monomers including amino acids, simple sugars, and nucleic acid bases. v 这些实验包括米勒等早期所做工作，成这些实验包括米勒等早期所做工作，成功地产出了有机单体，包括氨基酸，单糖，功地产出了有机单体，包括氨基酸，单糖，核酸碱基。核酸碱基。2022-7-626v The probable next step toward life was the spontaneous linking of s

25、uch monomers into polymers such as proteinoids and nuclei acids. v 这些单体自发的连接成多聚体，如类蛋白这些单体自发的连接成多聚体，如类蛋白和核酸，使进入生命状态成为可能。（和核酸，使进入生命状态成为可能。（使进入使进入生命状态成为可能的下一个步骤生命状态成为可能的下一个步骤）v Current research suggests that likely sites for this polymerization were clay or rock surfaces.v 目前的研究认为这些聚合作用可能发生在目前的研究认为这些聚合

26、作用可能发生在泥土或岩石表面。泥土或岩石表面。2022-7-627v Researchers have found that, when energy is available to a system, they can generate three kinds of organic molecular aggregates. v 研究发现当一个系统获得能量时，可能发生研究发现当一个系统获得能量时，可能发生3种有机分子的聚集体。种有机分子的聚集体。v The Russian Aleksandr Oparin obtained polymer-rich droplets, called coac

27、ervates, from solutions of polymers. v 俄国科学家从多聚物的溶液中获得了富含多俄国科学家从多聚物的溶液中获得了富含多聚物的小液滴，即凝聚物。聚物的小液滴，即凝聚物。2022-7-628v Sidney Fox generated proteinoid microspheres from mixtures of amino acid and water. vFox从氨基酸和水的混合液中获得了类蛋白微球从氨基酸和水的混合液中获得了类蛋白微球体。体。vA third laboratory structure is the liposome, a spherica

28、l lipid bilayer that forms from phospholipids.v 实验室第三个结构物质是脂质体，即由磷脂实验室第三个结构物质是脂质体，即由磷脂形成的球形液体脂双层结构。形成的球形液体脂双层结构。2022-7-629v A structure similar to one or more of these aggregates may have been the precursor of true cells.v与这些聚集体类似的结构可能是生命细胞与这些聚集体类似的结构可能是生命细胞的前体的前体. vFurther steps in the appearance o

29、f cells on the earth included the development of RNA and DNA as biological information molecules.v 地球上生命发生的下一阶段就是作为地球上生命发生的下一阶段就是作为生物信息分子的生物信息分子的 RNA 和和 DNA的形成。的形成。2022-7-630vEvidence suggests that RNA, which can form spontaneously under conditions mimicking those of the early earth, was the first i

30、nformation molecule.v 有证据表明有证据表明,在实验室模拟早期地球自然条件在实验室模拟早期地球自然条件下自发生成的下自发生成的RNA是最早的信息分子是最早的信息分子 。2022-7-631vThe discovery of RNA ribozymesRNA that can act as an enzymelike catalystsuggests that such catalytic RNA also could have assembled new RNAs from early nucleotides. v RNA核酶核酶- RNA可以作为类似酶的催化剂可以作为类似

31、酶的催化剂 - 的发现表明它可以催化早期核甘酸形成新的的发现表明它可以催化早期核甘酸形成新的RNA。vCertain catalytic RNAs can also carry out sexlike exchanges of pieces of RNA.v 某些催化性的某些催化性的RNA分子也能进行分子也能进行RNA片段间片段间性交换的。性交换的。2022-7-632v Following the development of a lipid-protein surface layer and replicating RNA and DNA informational molecules,

32、the events leading to the emergence of living cells would have the origin of the genetic code, the sequestering of RNA or DNA into cell-like structures, and the development of metabolic pathways.v 接下来脂蛋白表层的形成，信息分子接下来脂蛋白表层的形成，信息分子RNA和和DNA的的的的复制，最后导致活细胞发生，包括最初的遗传密码的确复制，最后导致活细胞发生，包括最初的遗传密码的确立，立，RNA或或DN

33、A被包裹进细胞样的结构中被包裹进细胞样的结构中,及代谢途径及代谢途径的建立。的建立。2022-7-633v The oldest fossils that may represent living cells are found in rocks that are about 3.5 billion years old.v能说明活细胞存在的最古老化石大约有能说明活细胞存在的最古老化石大约有35亿年了亿年了。v The first cells were probably anaerobic heterotrops, with autotrophs arising much later.v 最早出

34、现的细胞可能是厌氧异养生物，很最早出现的细胞可能是厌氧异养生物，很久后自养生物出现。久后自养生物出现。3. The earliest cells2022-7-634v The first autotrophs produced their own nutrients and released O2a metabolic by-product that had a crucial impact on later life forms. v 最早的自养生物可以制造营养物质并释放氧气最早的自养生物可以制造营养物质并释放氧气-这这个新陈代谢副产品对后期生命的形成有一个深远的影个新陈代谢副产品对后期生命

35、的形成有一个深远的影响。响。(这个是对后期生命的形成有一个深远的影响新陈这个是对后期生命的形成有一个深远的影响新陈代谢副产品。代谢副产品。)v The resulting ozone layer in the earths atmosphere reduced the penetration of ultraviolet light.v地球大气层中的臭氧层的出现减少了紫外线的照射。地球大气层中的臭氧层的出现减少了紫外线的照射。2022-7-635v As a result, cells would survive in shallow water and on the land surface

36、.v 结果，细胞就能够在浅水区和陆地上生存了。结果，细胞就能够在浅水区和陆地上生存了。v The increasing quantity of atmospheric oxygen also permitted the evolution of aerobic cells and cellular respiration, which in turn signaled the beginning of the global carbon cycle.v 大气中氧气数量的增加使得需氧细胞和细胞大气中氧气数量的增加使得需氧细胞和细胞呼吸得以进化，这预示着全球碳循环的开始。呼吸得以进化，这预示着全球

37、碳循环的开始。2022-7-636v Although the earliest cells were all prokaryotes, by about 1.5 billion years ago eukaryotes appeared.v虽然最早期的细胞都是原核生物，但虽然最早期的细胞都是原核生物，但是在大约是在大约15亿年前，真核细胞出现了。亿年前，真核细胞出现了。2022-7-6374. The changing face of planet earthvChanges in land masses, the seas, and climate have greatly affecte

38、d the evolution of life on the earth. v大陆板块，海洋和气候的变化对地球生命的进化大陆板块，海洋和气候的变化对地球生命的进化有深远的影响。有深远的影响。vThe basic parts of the planet include a light, solid crust over a hot, semisolid mantle and an inner, partially molten core. v地球的最基本的组分包括坚硬的地壳，半流体的地球的最基本的组分包括坚硬的地壳，半流体的地幔和熔解态的地核地幔和熔解态的地核2022-7-638vMassive

39、 segments or plates of the crust move over the mantle in the process of continental drift.v大板快地壳挤压地幔形成大陆漂移。大板快地壳挤压地幔形成大陆漂移。vOver the past 500 million years, continental drift hassculpted the earths crusts to produce the form anddistribution of present-day continents.v在过去的亿年里，大陆漂移雕塑了地壳的外观，在过去的亿年里，大陆漂

40、移雕塑了地壳的外观，从而形成了现在的大陆。从而形成了现在的大陆。2022-7-639vClimatic changes that greatly affected living organisms accompanied these plate movements; the period was marked by occasional waves of mass extinctions of living creatures.v伴随板块运动，气候改变对生物有深远影响，伴随板块运动，气候改变对生物有深远影响，在特定时期的生物大灭绝就是这个时期的见在特定时期的生物大灭绝就是这个时期的见证。证。2

41、022-7-640v Organisms were also affected by periods of glaciation that followed variations in the earths orbit and in the output of energy by the sun.v 生物也受冰河期影响，在冰河期，地球轨生物也受冰河期影响，在冰河期，地球轨道和太阳能的输出都发生了很大变化。道和太阳能的输出都发生了很大变化。2022-7-6415. taxonomy: categorizing the variety of living thingsvBiologists use

42、 the binomial system of nomenclature developed by Linnaeus to categorize the varieties of life on the earth. v生物学家利用林奈提出的双名法对地球上的生物生物学家利用林奈提出的双名法对地球上的生物进行分类。进行分类。 vThe system assigns each type of organism to a genus and species. v该系统可以将每种生物划分到属和种该系统可以将每种生物划分到属和种2022-7-642vOrganisms are then further classified into higher taxonomic categoriesfamily, order, class, division (plants), phylum (animals), and kingdom.v然后将生物进一步划分到更高级类别中，即然后将生物进一步划分到更高级类别中，即科，目，纲，门，界。科，目，纲，门，界。2022-7-643vEvidence from many subfields of biolog