1、Lesson One Inside the Living Cell: Structure and Function of Internal Cell Parts,Warmingup Words and phrases Text Analysis Simple exercises Additional Information,Contents,Warmingup,植物细胞模式图,动物细胞模式图,Glossary -about the proteins and organelles inside the living cell Structure and Function- about the o
2、rganelles inside the living cell,Focus in,A globular contractile protein. In muscle cells, actin interacts with another protein, myosin, to bring about contraction.,1. actin,n. 肌动蛋白,Words and phrases,2.,n肌球蛋白,肌动蛋白,3.,Microfilaments are solid rods made of a protein known as actin.,4.,Microtubules are
3、 biopolymers that are composed of subunits.,5. cytoskeleton,n细胞骨架,6. cytoplasm,n.胞质,7. centriole,n. 中心粒,An organelle located close to the nucleus in most animal and lower plant cells but absent from prokaryotes and higher plants.,8. chemotaxis,n. 动物 化学向性； 生物趋化现象；趋药性A locomotory movement of an organi
4、sm or cell in response to, and directed by, an external directional stimulus.,9.,A plastid in which photosynthesis is carried out. Chloroplasts occur in all photosynthetic organisms except photosynthetic bacteria and blue-green algae.,10.,A DNA-histone thread residing in the nucleus of a cell. Each
5、chromosome possesses two telomeres and a centromere, and some contain a nucleolus organizer.,11.,n. 纤毛,Numerous short, hairlike structures projecting from the cell surface that enable locomotion.,12.,13.,14.,15.,16.,n拟核，类核，核质体,17.,n核仁,18.,n胞核，神经核，核,19.,n吞噬作用,20.,21.,n.质体，成形粒,质体是植物细胞中由双层膜包裹的一类细胞器的总称，
6、可分为白色体、有色体和叶绿体。,22.,23.,24.,n子座；基质,25.,26.,27. endoplasmic reticulum,n. 内质网,The endoplasmic reticulum plays an important role in the biosynthesis, processing, and transport of proteins and lipids.,28. nuclear envelope,n. 核膜，核被膜,29. Golgi complex,n. 高尔基复合体,30. basal body,n. 基体,纤毛和鞭毛的微管组织中心,Words and
7、phrases:,Actin myosin centriole nucleoid chemotaxis nucleoli chloroplast nucleus chromosome phagocytosis cilia pinocytosis cytoplasm plastid cytoskeleton polysome dynein ribosome flagella stroma lysosome tubulin microfilament vacuole microtubule mitochondrion,1. Cytoplasm: The Dynamic, Mobile Factor
8、y,Most of the properties we associate with life are properties of the cytoplasm. Much of the mass of a cell consists of this semifluid substance, which is bounded to the outside by the plasma membrane. Organelles are suspended within it, supported by the filamentous network of the cytoskeleton. Diss
9、olved in the cytoplasmic fluid are nutients,ions, soluble proteins, and other materials needed for cell functioning.,参考翻译,1.细胞质：动力工厂与生命相关的大部分特性都来自于胞质中。绝大多数细胞都由这种质膜包被的半流体胞质组成。在胞质中悬浮着各种细胞器，并由丝状的细胞骨架所支撑。营养物质、金属离子、可溶性蛋白以及维持细胞生理需求的其他物质溶于胞质流体中。,2. The Nucleus: Information Central,The eukaryotic cell nucle
10、us is the largest organelle and house the genetic material (DNA) on chromosomes. ( In prokaryotes the hereditary material is found in the nucleoid). The nucleus also contains one or two organelles-the nucleoli-that play a role in cell division. A pore-perforated sac called the nuclear envelope separ
11、ates the nucleus and its contents from the cytoplasm. Small molecules can pass through the nuclear envelope, but larger molecules such as mRNA and ribosomes must enter and exit via the pores.,参考翻译 2.细胞核:信息中心在真核生物中，细胞核是最大的细胞器，细胞核的染色体上携带着遗传物质DNA（原核生物的遗传物质位于拟核中）。细胞核含有12个核仁，核仁主要在细胞分裂的过程中发挥作用。含有多个核孔的核膜将胞
12、核和胞质隔开，小分子物质能自由通过核膜，而大分子物质如mRNA、核糖体等则必须通过核孔穿梭于胞质和胞核中。,3. Organelles: Specialized Work Units,All eukaryotic cells contain most of the various kinds organelles, and each organelle performs a specialized function in the cell. Organelles described in this section include ribosomes, the endoplasmic retic
13、ulum, the Golgi complex, Vacuoles, lysosomes, mitochondria, and the plastids of plant cells.,参考翻译 3.细胞器:各司其职所有的真核生物都包含着多种细胞器，每一种细胞器又行使着不同的功能。本文主要介绍核糖体、内质网、高尔基体、液泡、溶酶体、线粒体和植物细胞中的质体等。,The number of ribosomes within a cell may range from a few hundred to many thousands. This quantity reflects the fact
14、that ribosomes are the sites at which amino acids are assembled into proteins for export or for use in cell processes. A complete ribosome is composed of one larger and one smaller subunit. During protein synthesis the two subunits move along a strand of mRNA, “reading” the genetic sequence coded in
15、 it and translating that sequence into protein. Several ribosomes may become attached to a single mRNA strand; Such a combination is called a polysome. Most cellular proteins are manufactured on ribosomes in the cytoplasm. Exportable proteins and membrane proteins are usually made in association wit
16、h the endoplasmic reticulum.,参考翻译细胞中核糖体的数量往往从几百到几千不等，数量之众反映出在细胞加工过程中核糖体提供了氨基酸装配合成蛋白质的场所，合成的蛋白就地使用或运到别处。完整的核糖体由大、小两个亚基组成。在蛋白质合成的过程中，两个亚基沿着mRNA移动，读取mRNA上编码的遗传信息并将其翻译成蛋白。几个核糖体往往串连到一条mRNA单链上，这样形成的复合体叫做多聚核糖体。大多数细胞蛋白是由细胞质中核糖体合成，转运蛋白和膜蛋白的合成则通常与内质网有关。,The endoplasmic reticulum, a lacy array of membranous sa
17、cs, tubules, and vesicles, may be either rough (RER) or smooth (SER). Both types play roles in the synthesis and transport of proteins. The RER, which is studded with polysomes, also seems to be the source of the nuclear envelope after a cell divides. The SER lacks polysomes; it is active in the syn
18、thesis of fats and steroids and in the oxidation of toxic substances in the cell. Both types of endoplasmic reticulum serve as compartments within the cell where specific products can be isolated and subsequently shunted to particular areas in or outside the cell.,参考翻译内质网是一个连续的膜囊和膜管网，可分为粗糙内质网和光滑内质网两
19、种类型，两种都与蛋白质的合成和运输有关。其中的糙面内质网上附着多聚核糖体，它可能是细胞分裂后形成核膜的来源；光面内质网无多聚核糖体，主要作用是脂肪和类固醇的合成以及细胞内有毒物质的氧化。总之，两种类型的内质网都可以发挥隔离室的作用，相关产物在其中进行分流或运输到细胞外。,Transport vesicles may carry exportable molecules from the endoplasmic reticulum to another membranous organelle, the Golgi complex. Within the Golgi complex molecu
20、les are modified and packaged for export out of the cell or for delivery else where in the cytoplasm.,参考翻译转运囊泡能够将转运分子从内质网转运到其他的膜包被的细胞器（高尔基体）中，在高尔基复合体中修饰，包装后输出细胞或传递到细胞质中的其他场所。,Vacuoles in cells appear to be hollow sacs but are actually filled with fluid and soluble molecules. The most prominent vacuo
21、les appear in plant cells and serve as water reservoirs and storage sites for sugars and other molecules. Vacuoles in animal cells carry out phagocytosis (The intake of particular matter) and pinocytosis (vacuolar drinking).,参考翻译液泡看似一个空囊，实则充满了流质和可溶性分子。大液泡存在于植物细胞中，储留水分、糖分和其他分子。动物细胞中的液泡主要起胞吞和胞饮的功能。,A
22、subset of vacuoles is the organelles known as lysosomes, which contain digestive enzymes (packaged in lysosomes in the Golgi complex) that can break down most biological macromolecules. They act to digest food particles and to degrade damaged cell parts.,参考翻译溶酶体是液泡的亚单位，其中含有的多种消化酶是由高尔基体包装转运的。这些消化酶能够降
23、解大多数生物大分子、食物颗粒和损伤的细胞碎片。,Mitochondria are the sites of energy-yielding chemical reactions in all cells. In addition, plant cells contain plastids that utilize light energy to manufacture carbohydrates in the process of photosynthesis. It is on the large surface area provided by the inner cristae of m
24、itochondria that ATP-generating enzymes are located. Mitochondria are self-replicating, and probably they are the evolutionary descendants of what were once free-living prokaryotes.,参考翻译线粒体是所有细胞中细胞中化学产能的场所。另外，植物细胞中的质体在光合作用中利用光能产生碳水化合物。线粒体内嵴上提供了很大的表面积并分布着产ATP酶。线粒体自我复制，可能是独立生存的原核生物在进化中形成的后代。,There are
25、 two types of plastids: Leucoplasts, which lack pigments and serve as storage sites for starch, proteins, and oils; and chromoplasts, which contain pigments. The most important chromoplasts are chloroplasts-organelles that contain the chlorophyll used in photosynthesis. The internal structure of chl
26、oroplasts includes stacks of membranes called grana, which are embedded, in a matrix called the stroma.,参考翻译质体有两种类型，分别是白色体和有色体。白色体不含色素，是淀粉、蛋白质、油脂的储存库；有色体含有色素，其中最重要的一类是叶绿体。叶绿体含有光合作用所需的叶绿素，其内部结构由基质和嵌入其中基粒（膜包被的类囊体垛叠在一起）组成。,4. The cytoskeleton,All eukaryotic cells have a cytoskeleton, which is a convolu
27、ted latticework of filaments and tubules that appears to fill all available space in the cell and provides support for various other organelles. A large portion of the cytoskeleton consists of threadlike microfilament composed mainly of the contractile protein actin. They are involved in many types
28、of intracellular movements in plant and animal cells. A second protein, myosin, is involve in the contraction of muscle cells.,参考翻译4.细胞骨架所有的真核生物都有细胞骨架，细胞骨架是由细丝和小管形成的交错盘旋的网格结构，这种结构几乎充斥了细胞中所有可利用的空间并且对细胞器提供支持作用。细胞骨架主要由微丝组成，微丝主要是可伸缩的肌动蛋白。动植物细胞的许多种类型细胞内运动与肌动蛋白有关。第二类蛋白是肌球蛋白，它与肌肉细胞的收缩有关。,Another main struc
29、tural component of the cytoskeleton consists of microtubules, which are composed of the globular protein tubulin and together act as scaffolding that provides a stable cell shape.,细胞骨架的另一个主要的结构成分是微管，它由球状微管蛋白组成，起稳定细胞形态的支架作用。,Cytoskeletal intermediate filaments appear to impart tensile strength to the
30、 cell cytoplasm. Mechanoenzymes such as myosin, dynein, and kinesin interact with the cytockeletal filaments and tubules to generate forces that cause movements.,细胞骨架的中间纤维提供了细胞质伸缩动力。 “机械酶”类如肌球蛋白、动力蛋白、驱动蛋白与微丝和微管相互作用从而产生动力，驱动细胞运动。,5. Cellular movements 细胞运动,Although the cytoskeleton provides some stab
31、ility to cells, its microtubules and filaments and their associated proteins enable cells to move by creeping or gliding.,尽管细胞骨架提供了细胞的某些稳定性，微管、微丝及其相关蛋白却仍能够使细胞以爬行或滑翔的方式运动。,Such movements require a solid substrate to which the cell can adhere and can be guided by the geometry of the surface.,这种运动需要一个能
32、使细胞附着的固体基质，并通过表面几何形状的改变而运动。,Some cells also exhibit chemotaxis, the ability to move toward or away from the source of a diffusing chemical.,有些细胞还表现出趋化能力，即趋向或逃离扩散开的化学源。,Certain prokaryotic cells can swim freely in liquid environments, propelled by whiplike cilia or flagella.,某些原核细胞可在液体环境中通过鞭子似的纤毛或鞭毛推
33、动进行自由地泳动。,Both cilia and flagella have the same internal structure: nine doublets(pairs of microtubules) are arranged in a ring and extend the length of the cilium or flagellum, and two more microtubules run down the center of the ring.,纤毛和鞭毛具有相同的内部结构：9对微管排列成环沿纤毛或鞭毛长轴延长，另有两根或两根以上微管在环的中央位置。,Every cil
34、ium or flagellum grows only from the cell surface where a basal body is located. Movement is based on the activities of tiny dynein side arms that extend from one of the microtubules of each doublet.,纤毛或鞭毛自细胞表面的基体长出，其运动基于每个联管上的一个微管延伸出的由微小的动力蛋白的形成的臂。,Nutrients, proteins, and other materials within mo
35、st plant cells are moved about via cytoplasmic streaming.,大多数植物细胞内部的营养物质、蛋白质和其它物质通过胞质流动进行运动。,The process occurs as myosin proteins attached to organelles push against microfilaments arrayed throughout the cell. Microfilaments and microtubules are responsible for almost all major cytoplasmic movement
36、s.,这个过程伴随附着在细胞器上的肌球蛋白推动遍布于整个细胞中的微丝而发生。,微丝和微管负责几乎所有主要的胞质内运动。,During cell division, microtubules of the spindleassembled from tubulin subunits near organelles called centriolesmove the chromosomes.,在细胞分裂期间，靠近中心粒的微管蛋白亚基装配成纺锤体的微管，这些微管负责染色体的移动。,Review the words:,Actin -肌动蛋白 centriole -中心粒 chemotaxis -趋化性
37、 chloroplast -叶绿体 chromosome -染色体 cilia -纤毛 Cytoplasm-胞质 cytoskeleton -细胞骨架 flagella-鞭毛 lysosome -溶酶体 microfilament -微丝 microtubule -微管 mitochondrion -线粒体,myosin -肌球蛋白 nucleoid -拟核 nucleoli -核仁 nucleus-细胞核 phagocytosis -吞噬作用 pinocytosis- 胞饮作用 plastid -质体 polysome -多聚核糖体 dynein -动力蛋白 stroma -基质 lysos
38、ome -溶酶体 vacuole -液泡,Exercises,I Key terms: matching,Match each term on the left with the most appropriate description on the right,Polysome a. protein synthesis Pinocytosis b.baglike structure Exocytosis c. power generator Plastid d. where flagella grow Golgi complex e.toward or away from a chemica
39、l stimulus Flagella f. engulfment Phagocytosis g.RNA and ribosomes Lysosome h. weblike Basal body i. in plants only Chemotactic j. control room Nucleus k. expel Vacuole l. vacant Ribosome m. whiplike Cytoskeleton n. cell drinking Mitochondrion o. packaging,II. True or false,The DNA of prokaryotic ce
40、ll is concentrated in the nucleus. 2. Ribosomes are derived from the nucleoli. 3. Unlike other cell membranes, the nuclear envelope has no pores. 4. The smooth endoplasmic reticulum is held in place by the cytoskeleton. 5. Structural proteins are exportable. 6. The nuclear envelope is produced by th
41、e rough endoplasmic reticulum.,7. Most cellular proteins are manufactured on ribosomes. 8. White blood cells work by phagocytosis. 9. Prokaryotic cells have microbodies. 10. Mitochondria are self-replication. 11. Pinocytosis describes the intake of fluid into a a cell by a vacuole. 12. Both prokaryo
42、tic and eukaryotic cells have a supporting cytoskeleton. 13. Carotenoids （类胡萝卜素） are colorless molecules. 14. Grana （基粒）are surrounded by stomata（气孔）.,III Completion,Phagocytosis is a method of cell feeding that first requires that the food be 2. The packages some fifty hydrolytic enzyme in are lyso
43、some-like vesicles containing waste products. They are thought to involved with cell Both and thought to have arisen from endosymbiosis.(内共生),engulfed,Golgi complex,lysosomes,Lipofuscin granules（脂褐质颗粒）,aging,mitochondria,Chloroplasts,III Completion,5. The cytoskeleton is composed of very fine , medi
44、um and larger 6. Creeping and gliding cell movements are usually -dependent. 7. Behavior is shown when a cell moves toward or away from a chemical substance. 8. Glagella grow from the cell surface only at the,microfilaments,Intermediate filaments,microtubules,anchorage,Chemotactic,basal body,IV Mult
45、iple choice,1. Most of the properties associated with processes of life are properties of_. A. The nucleus B. DNA C. The cytoplasm D. endosymbionts E. None of the above,2. Ribosmes_. A. are organelles involved in protein synthesis B. are the cells sites for starch C. are involved in the breakdown of
46、 proteins D. are the cells main energy source E. None of the above,3. Smooth endoplasmic reticulum(SER) _. A. Lacks ribosomes B. is acive in fat and steroid synthesis C. is involved in the oxidiation of toxins D. all of the above E. none of the above,4. ribosomes are manufactured in _. A. cytoplasm B. nucleoli C. mitochondria D. SER E. RER,
