English for BiologyStudents Lesson one Reading Materials

1、English for Biology Students 生物專業(yè)英語Lesson one Reading MaterialsType type of 類型 new type 新型 type in 打入，輸入 same type 同型 data type 數(shù)據(jù) 資料類型 structure type 結(jié)構(gòu)類型 type selection 典型選擇 special type 特種；特殊型；特殊型號的設(shè)備 2.The Biological World Has Two Types Of Cells生物界有兩種細(xì)胞類型生物界有兩種細(xì)胞類型 There are actually two differe

2、nt types of cells in the biological world, cells with a nucleus and cells that lack one. 其實，在生物界中有兩種不同的細(xì)胞類型，有核細(xì)胞和無核細(xì)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. 無核細(xì)胞，又稱為原核細(xì)胞，沒有內(nèi)部隔層（沒有核膜），因此，細(xì)胞中有基因功能與其他功能的無縫耦合。原核細(xì)胞進(jìn)化形成于其他的細(xì)胞前，現(xiàn)今的細(xì)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. 真核細(xì)胞，有細(xì)胞核，是進(jìn)化

4、后的產(chǎn)物，他們顯示了更多復(fù)雜的基因調(diào)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. 真核細(xì)胞的細(xì)胞核被核膜包圍細(xì)胞的DNA，把基因和構(gòu)成細(xì)胞質(zhì)的其余細(xì)胞分離。 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. 這就讓細(xì)胞質(zhì)中DNA的功能和其他的解耦和，也讓復(fù)雜的基因調(diào)控過程進(jìn)化。in turn 反過來； 依次，挨個； 交替地，輪流地 ；by turns , in file 輪流，依次in turn 轉(zhuǎn)而，反過來，依次in return 作為回報Can I buy lunch for you in return for your help?感謝你的幫忙，我請你吃午飯好么？I asked her opinion,but she just asked me a question in t

6、urn.我征求她的意見，她卻只是反問了一個問題。 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. 真核細(xì)胞里所有的多細(xì)胞生物都是聚集形成的，通常是高度專業(yè)化，但也有許多單細(xì)胞生物有核，酵母菌細(xì)胞就是其中的一個例子。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. 真核細(xì)胞不僅有一個核，而且在進(jìn)化過程中也被賦予了他們其他細(xì)胞內(nèi)的隔層稱為細(xì)胞器。 For instance, they have lysosomes, which are membrane-limited compartments specialized f

8、or carrying out degradative processes. 例如，他們有溶酶體，專門為了降解過程的膜有限的車廂。 Each of the many types of organelles in eukaryotic cells is devoted to a particular set of functions. 在真核細(xì)胞里眾多種類的細(xì)胞器中，每一種都是有專門的特定的功能。be devoted to doing 獻(xiàn)身于 ; 致力于 ; 熱衷于 be devoted to sb 喜歡某人 be devoted to duty 遵守規(guī)則 eg.Only when we rea

9、lize the importance of helping each other can we be devoted to building a harmonious society. 只有當(dāng)我們意識到互相幫助的重要性,我們才能致力于建設(shè)一個和諧社會. 3.Membranes Serve Functions Other Than Segregation膜提供隔離以外的功能膜提供隔離以外的功能 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 . 膜除了作為一種分離細(xì)胞內(nèi)部水環(huán)境和周圍環(huán)境的一種方法，或用來分離細(xì)胞與細(xì)胞，他們還有其他重要的功能；一方面，他們存儲能量。 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 . 由于膜有隔離細(xì)胞內(nèi)水艙的作用，如果一個離子或分子溶解在水中要穿過膜移動進(jìn)入一個新的細(xì)胞區(qū)室，它是不能自由移動擴(kuò)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 . 分子移動需要耗能，之后分子貯存能量通過截留的功能。 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 . 正式的說，能量儲存就像是電池的能源儲存；因此，膜不僅作為細(xì)胞

13、的界膜，而且他們還是細(xì)胞活動的積極參與者。 Another function of membranes is to act as anchors for molecules ,the primarily proteins .these proteins have functions that require membrane -binding . 膜的另一個功能是充當(dāng)固定分子的作用，主要是蛋白質(zhì)。這些蛋白質(zhì)的功能需要膜結(jié)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，水溶性分子通過膜通道的轉(zhuǎn)運是鑲嵌在細(xì)胞膜間進(jìn)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 . 同時，細(xì)胞通過釋放信號分子

15、發(fā)送信息給對方。細(xì)胞外膜的蛋白質(zhì)，是已知的特定的的受體，用于結(jié)合循環(huán)的信號分子。 These signaling molecules allow the individual activities of the many cells in the body to be coordinated . 這些信號分子讓體內(nèi)的許多細(xì)胞個體活動保持協(xié)調(diào). 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 . 通過受體的信號分子引起的細(xì)胞內(nèi)蛋白質(zhì)發(fā)生特定類型的瞬態(tài)組織變化，稱為蛋白的信號轉(zhuǎn)導(dǎo)，在細(xì)胞膜的內(nèi)表面為活化絡(luò)合物，它是在細(xì)胞的細(xì)胞質(zhì)或細(xì)胞核發(fā)生改變。4.Eukaryotic cells contain o

17、rganelles thought to have evolved as independent organisms真核細(xì)胞真核細(xì)胞被認(rèn)為是含有細(xì)胞器的獨立的有機(jī)體被認(rèn)為是含有細(xì)胞器的獨立的有機(jī)體 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 .在植物細(xì)胞中葉綠體，另一個顯著

18、的是，有核細(xì)胞在進(jìn)化過程中發(fā)生成為能源生產(chǎn)的線粒體是細(xì)菌的作用意義。 in todays world these organelles of the cell are dependent on functions encoded in the nucleus . 在當(dāng)今生物界，這些細(xì)胞的細(xì)胞器是依賴于細(xì)胞核編碼的功能。 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 . 不管怎樣，他們保留自己的一些基因功能，所以，現(xiàn)今有核細(xì)胞的多基因系統(tǒng)：主要由核和輔助系統(tǒng)（他們自己線粒體和葉綠體中的DNA）來控制系統(tǒng)。 In the organelles ,the