English for BiologyStudents Lesson one Reading Materials

1、English for Biology Students 生物专业英语Lesson one Reading MaterialsType type of 类型 new type 新型 type in 打入，输入 same type 同型 data type 数据 资料类型 structure type 结构类型 type selection 典型选择 special type 特种；特殊型；特殊型号的设备 2.The Biological World Has Two Types Of Cells生物界有两种细胞类型生物界有两种细胞类型 There are actually two differe

2、nt types of cells in the biological world, cells with a nucleus and cells that lack one. 其实，在生物界中有两种不同的细胞类型，有核细胞和无核细胞. The anuclear cells, called prokaryotic cells, have no internal compartments and therefore, in them, there is a seamless coupling of gene function with other events in the cell. Prok

3、aryotic cells evolved before others and are the bacteria of today. 无核细胞，又称为原核细胞，没有内部隔层（没有核膜），因此，细胞中有基因功能与其他功能的无缝耦合。原核细胞进化形成于其他的细胞前，现今的细菌就是原核生物。 Eukaryotic cells, those that have a nucleus, are later products of evolution, and they display much more complicated modes of gene regulation. 真核细胞，有细胞核，是进化

4、后的产物，他们显示了更多复杂的基因调控模式。 The nucleus surrounds the cells DNA with a specialized membrane, segregating the genes from the rest of the cell that constitutes the cytoplasm. 真核细胞的细胞核被核膜包围细胞的DNA，把基因和构成细胞质的其余细胞分离。 This allows the functions of DNA to be uncoupled from events in the cytoplasm, which, in turn,

5、 allows the evolution of complex gene regulatory processes. 这就让细胞质中DNA的功能和其他的解耦和，也让复杂的基因调控过程进化。in turn 反过来； 依次，挨个； 交替地，轮流地 ；by turns , in file 轮流，依次in turn 转而，反过来，依次in return 作为回报Can I buy lunch for you in return for your help?感谢你的帮忙，我请你吃午饭好么？I asked her opinion,but she just asked me a question in t

6、urn.我征求她的意见，她却只是反问了一个问题。 All multicellular organisms are formed of aggregated, often highly specialized, eukaryotic cells, but there are also many unicellular organisms with nuclei; yeast cells are an example. 真核细胞里所有的多细胞生物都是聚集形成的，通常是高度专业化，但也有许多单细胞生物有核，酵母菌细胞就是其中的一个例子。be formed of 由形成In the form of;

7、in the shape of 以.的形式 Eukaryotic cells not only have a nucleus, but evolutionary processes have also endowed them with other intracellular compartments called organelles. 真核细胞不仅有一个核，而且在进化过程中也被赋予了他们其他细胞内的隔层称为细胞器。 For instance, they have lysosomes, which are membrane-limited compartments specialized f

8、or carrying out degradative processes. 例如，他们有溶酶体，专门为了降解过程的膜有限的车厢。 Each of the many types of organelles in eukaryotic cells is devoted to a particular set of functions. 在真核细胞里众多种类的细胞器中，每一种都是有专门的特定的功能。be devoted to doing 献身于 ; 致力于 ; 热衷于 be devoted to sb 喜欢某人 be devoted to duty 遵守规则 eg.Only when we rea

9、lize the importance of helping each other can we be devoted to building a harmonious society. 只有当我们意识到互相帮助的重要性,我们才能致力于建设一个和谐社会. 3.Membranes Serve Functions Other Than Segregation膜提供隔离以外的功能膜提供隔离以外的功能 Although membranes are valuable as a way to segregate the water interior of the cell from its environ

10、ment , or to segregate intracellular events from one another ,they have other important functions ; for one thing ,they make energy storage possible . 膜除了作为一种分离细胞内部水环境和周围环境的一种方法，或用来分离细胞与细胞，他们还有其他重要的功能；一方面，他们存储能量。 Because membranes separate watery compartments from one another ,if an ion or a molecul

11、e dissolved in water is moved through a membrane into a new cellular compartment ,it will not be able to freely diffuse out of the compartment into which it was moved . 由于膜有隔离细胞内水舱的作用，如果一个离子或分子溶解在水中要穿过膜移动进入一个新的细胞区室，它是不能自由移动扩散到室的。 It takes energy to move the molecule but ,once moved ,the molecule sto

12、res that energy by virtue of its entrapment . 分子移动需要耗能，之后分子贮存能量通过截留的功能。 Formally ,this storage of energy is just like the storage of energy in a battery ;therefore ,membranes not only delineate compartments ,but also they are active participants in the cells dynamism . 正式的说，能量储存就像是电池的能源储存；因此，膜不仅作为细胞

13、的界膜，而且他们还是细胞活动的积极参与者。 Another function of membranes is to act as anchors for molecules ,the primarily proteins .these proteins have functions that require membrane -binding . 膜的另一个功能是充当固定分子的作用，主要是蛋白质。这些蛋白质的功能需要膜结合。 For instance ,the passage of water -soluble molecules through membranes is carried ou

14、t by transporters that are embedded in the membrane . 例如，水溶性分子通过膜通道的转运是镶嵌在细胞膜间进行的。 Also ,cells send information to each other by releasing signaling molecules .The outer membranes of cells have proteins ,known appropriately as receptors ,which bind the circulating signaling molecules . 同时，细胞通过释放信号分子

15、发送信息给对方。细胞外膜的蛋白质，是已知的特定的的受体，用于结合循环的信号分子。 These signaling molecules allow the individual activities of the many cells in the body to be coordinated . 这些信号分子让体内的许多细胞个体活动保持协调. The receipt of a signaling molecule by a receptor causes the transient organization of particular types of intracellular protei

16、ns ,called signal transduction proteins ,into an activated complex at the interior face of the cells outer membrane ,from which it directs alterations of events in the cells cytoplasm or nucleus . 通过受体的信号分子引起的细胞内蛋白质发生特定类型的瞬态组织变化，称为蛋白的信号转导，在细胞膜的内表面为活化络合物，它是在细胞的细胞质或细胞核发生改变。4.Eukaryotic cells contain o

17、rganelles thought to have evolved as independent organisms真核细胞真核细胞被认为是含有细胞器的独立的有机体被认为是含有细胞器的独立的有机体 Another striking event that occurred during the evolution of nucleated cells was the import of bacteria to become their energy -producing mitochondria and ,in plant cells ,chloroplasts .在植物细胞中叶绿体，另一个显著

18、的是，有核细胞在进化过程中发生成为能源生产的线粒体是细菌的作用意义。 in todays world these organelles of the cell are dependent on functions encoded in the nucleus . 在当今生物界，这些细胞的细胞器是依赖于细胞核编码的功能。 However ,they retain some genetic functions of their owm ,so that nucleated cells today have multiple genetic systems in them :a predominant system controlled from the nucleus and secondary systems with their own DNA in the mitochondria and chloroplasts . 不管怎样，他们保留自己的一些基因功能，所以，现今有核细胞的多基因系统：主要由核和辅助系统（他们自己线粒体和叶绿体中的DNA）来控制系统。 In the organelles ,the