第一篇：蔣悟生《生物專業(yè)英語(yǔ)》教學(xué)案

蔣悟生《生物專業(yè)英語(yǔ)》教/學(xué)案

Lesson One（4學(xué)時(shí)）Inside the Living Cell: Structure andFunction of Internal Cell Parts

Lesson One（4學(xué)時(shí)）

Inside the Living Cell: Structure andFunction of Internal Cell Parts

教學(xué)目的：使學(xué)生掌握細(xì)胞的組成結(jié)構(gòu)（各種細(xì)胞器以及它們?cè)诩?xì)胞中的位置），以及結(jié)構(gòu)與功能之間的關(guān)系。各細(xì)胞器及功能相關(guān)英語(yǔ)詞匯以及主要用法。

教學(xué)重點(diǎn)：各細(xì)胞器的概念和功能，及相關(guān)英語(yǔ)詞匯的掌握 教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：3月22日；3月29日 教學(xué)內(nèi)容：

Cytoplasm: The Dynamic, Mobile Factory 細(xì)胞質(zhì)：動(dòng)力工廠

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 on the outside by the plasma membrane.Organelles are suspended within it, supported by the filamentous network of the cytoskeleton.Dissolved in the cytoplasmic fluid are nutrients, ions, soluble proteins, and other materials needed for cell functioning.生命的大部分特征表現(xiàn)在細(xì)胞質(zhì)的特征上。細(xì)胞質(zhì)大部分由半流體物質(zhì)組成，并由細(xì)胞膜（原生質(zhì)膜）包被。細(xì)胞器懸浮在其中，并由絲狀的細(xì)胞骨架支撐。細(xì)胞質(zhì)中溶解了大量的營(yíng)養(yǎng)物質(zhì)，離子，可溶蛋白以及維持細(xì)胞生理需求的其它物質(zhì)。

The Nucleus: Information Central（細(xì)胞核：信息中心）

The eukaryotic cell nucleus is the largest organelle and houses 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 separates 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.真核細(xì)胞的細(xì)胞核是最大的細(xì)胞器，細(xì)胞核對(duì)染色體組有保護(hù)作用（原核細(xì)胞的遺傳物質(zhì)存在于擬核中）。細(xì)胞核含有一或二個(gè)核仁，核仁促進(jìn)細(xì)胞分裂。核膜貫穿許多小孔，小分子可以自由通過(guò)核膜，而象mRNA和核糖體等大分子必須通過(guò)核孔運(yùn)輸。

Organelles: Specialized Work Units（細(xì)胞器：特殊的功能單位）

All eukaryotic cells contain most of the various kinds of organelles, and each organelle performs a specialized function in the cell.Organelles described in this section include ribosomes, the endoplasmic reticulum, the Golgi complex, vacuoles, lysosomes, mitochondria, and the plastids of plant cells.所有的真核細(xì)胞都含有多種細(xì)胞器，每個(gè)細(xì)胞器都有其特定功能。本節(jié)主要介紹核糖體，內(nèi)質(zhì)網(wǎng)，高爾基體系，液泡，溶酶體，線粒體和植物細(xì)胞中的質(zhì)體。The number of ribosomes within a cell may range from a few hundred to many thousands.This quantity reflects the fact 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 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 with the endoplasmic reticulum.核糖體的數(shù)量變化從幾百到幾千，核糖體是氨基酸組裝成蛋白質(zhì)的重要場(chǎng)所。完整的核糖體由大亞基和小亞基組成。核糖體沿著mRNA移動(dòng)并閱讀遺傳密碼，翻譯成蛋白質(zhì)。一條mRNA上可能有多個(gè)核糖體，稱多聚核糖體。大多數(shù)細(xì)胞蛋白是由細(xì)胞質(zhì)中核糖體生產(chǎn)。輸出蛋白和膜蛋白通常與內(nèi)質(zhì)網(wǎng)有關(guān)。

The endoplasmic reticulum, a lacy array of membranous sacs, 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.內(nèi)質(zhì)網(wǎng)，帶有花邊的生物囊，有管狀，泡狀之分，以及光滑和粗糙面區(qū)別。兩種都與蛋白質(zhì)的合成和運(yùn)輸有關(guān)。粗糙內(nèi)質(zhì)網(wǎng)上分布許多核糖體，也可能提供細(xì)胞分裂后所需的細(xì)胞膜。

SER lacks polysomes;it is active in the synthesis 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.光滑內(nèi)質(zhì)網(wǎng)上無(wú)核糖體，主要作用是脂肪和類固醇的合成以及細(xì)胞內(nèi)有毒物質(zhì)的氧化。兩種內(nèi)質(zhì)網(wǎng)合成的產(chǎn)物在其中進(jìn)行分流或運(yùn)輸?shù)郊?xì)胞外。

Transport vesicles may carry exportable molecules from the endoplasmic reticulum to another membranous organelle, the Golgi complex.Within the Golgi complex molecules are modified and packaged for export out of the cell or for delivery else where in the cytoplasm.運(yùn)輸小泡能夠?qū)⒖蛇\(yùn)輸分子從內(nèi)質(zhì)網(wǎng)運(yùn)輸?shù)礁郀柣鶑?fù)合體上。在高爾基復(fù)合體中修飾，包裝后輸出細(xì)胞或傳遞到細(xì)胞質(zhì)中的其他場(chǎng)所。

Vacuoles in cells appear to be hollow sacs but are actually filled with fluid and soluble molecules.The most prominent vacuoles 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 particulate matter)and pinocytosis(vacuolar drinking).細(xì)胞中的液泡好象是中空的，但實(shí)際上充滿了液體和可溶分子。最典型的液泡存在于植物細(xì)胞中，儲(chǔ)備水，糖以及其它分子。動(dòng)物中的液泡起吞噬和胞飲作用。

A subset of vacuoles are 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.溶酶體是液泡亞單位，含有消化酶，降解大部分生物大分子。消化食物微粒和降解損傷的細(xì)胞殘片。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 mitochondria that ATP-generating enzymes are located.Mitochondria are self-replicating, and probably they are the evolutionary descendants of what were once free-living prokaryotes.線粒體是細(xì)胞中化學(xué)產(chǎn)能的場(chǎng)所。另外，植物細(xì)胞中的質(zhì)體在光合作用中利用光能產(chǎn)生碳水化合物，線粒體內(nèi)嵴上提供了很大的表面積并分布著產(chǎn)ATP酶。線粒體自我復(fù)制，并且可能是自由生活的原核生物在進(jìn)化中形成的后代。There are 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 chloroplasts includes stacks of membranes called grana, which are embedded in a matrix called the stroma.質(zhì)體有兩種類型：白色體，缺乏色素，是淀粉，蛋白質(zhì)和油的儲(chǔ)備場(chǎng)所；色質(zhì)體，含有色素。葉綠體是最重要的色質(zhì)體，含有與光合作用有關(guān)的葉綠素。葉綠體的內(nèi)部結(jié)構(gòu)是由多層膜形成的葉綠體基粒，其中包埋在基質(zhì)中的基粒稱子座。The Cytoskeleton（細(xì)胞骨架）

All eukaryotic cells have a cytoskeleton, which is a convoluted 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 microfilaments composed mainly of the contractile protein actin.They are involved in many types of intracellular movements in plant and animal cells.A second protein, myosin, is involve in the contraction of muscle cells.Another main structural 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.Cytoskeletal intermediate filaments appear to impart tensile strength to the cell cytoplasm.Mechanoenzymes such as myosin, dynein, and kinesin interact with the cytoskeletal filaments and tubules to generate forces that cause movements.所有的細(xì)胞都有細(xì)胞骨架，網(wǎng)絡(luò)結(jié)構(gòu)的纖絲充滿了它所能觸及的全部空間并且對(duì)細(xì)胞器提供支持作用。細(xì)胞骨架大部分由微絲組成，微絲主要由可收縮的肌動(dòng)蛋白組成。動(dòng)植物細(xì)胞的許多種類型細(xì)胞內(nèi)運(yùn)動(dòng)與肌動(dòng)蛋白有關(guān)。第二類蛋白是肌球蛋白，它與肌肉細(xì)胞的收縮有關(guān)。細(xì)胞骨架的另一個(gè)主要結(jié)構(gòu)成分是微管，由球狀的微管蛋白組成，象腳手架一般維持細(xì)胞的穩(wěn)定形態(tài)。細(xì)胞骨架的中間絲提供了細(xì)胞質(zhì)伸縮動(dòng)力。機(jī)械酶，例如，肌球蛋白，動(dòng)力蛋白，驅(qū)動(dòng)蛋白與微絲，微管相互作用產(chǎn)生動(dòng)力而引起細(xì)胞運(yùn)動(dòng)。Cellular Movements（細(xì)胞運(yùn)動(dòng)）

Although the cytoskeleton provides some stability to cells, its microtubules and filaments and their associated proteins enable cells to move by creeping or gliding.Such movements require a solid substrate to which the cell can adhere and can be guided by the geometry of the surface.Some cells also exhibit chemotaxis, the ability to move toward or away from the source of a diffusing chemical.盡管細(xì)胞骨架提供了細(xì)胞的某些穩(wěn)定性，微絲，微管及相關(guān)蛋白能使細(xì)胞爬行或滑動(dòng)。這種運(yùn)動(dòng)需要固體基質(zhì)依托并通過(guò)表面幾何形狀的改變而運(yùn)動(dòng)。某些細(xì)胞具備趨藥性，即趨向或逃離擴(kuò)散開(kāi)的化學(xué)源。Certain eukaryotic cells can swim freely in liquid environments, propelled by whiplike cilia or flagella.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.Every cilium 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.某些真核細(xì)胞能在液體液體中自由運(yùn)動(dòng)，由纖毛或鞭毛推動(dòng)。纖毛和鞭毛具有同樣的內(nèi)部結(jié)構(gòu)：九個(gè)雙微管環(huán)形排列，縱向延伸，環(huán)中心是兩個(gè)或以上微管組成。纖毛或鞭毛從細(xì)胞表面的基體出生長(zhǎng)，雙微管的動(dòng)力蛋白臂從一側(cè)延伸到另一側(cè)而引起運(yùn)動(dòng)。

Nutrients, proteins, and other materials within most plant cells are moved about via cytoplasmic streaming.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 movements.During cell division, microtubules of the spindle assembled from tubutin subunits near organelles called centrioles move the chromosomes.大部分植物細(xì)胞的營(yíng)養(yǎng)，蛋白質(zhì)和其它物質(zhì)由細(xì)胞質(zhì)流運(yùn)輸。這個(gè)過(guò)程是由于依附在細(xì)胞器上的肌球蛋白反推排列在細(xì)胞周?chē)奈⒔z形成的。絕大部分細(xì)胞質(zhì)運(yùn)動(dòng)由微絲和微管完成。在細(xì)胞分裂期間，中心粒周?chē)挠晌⒐艿鞍讈喕b配形成的紡錘體微管移向染色體。課后作業(yè)：第一第二篇閱讀材料

答案：1B,2C,3B,4B,5D,6c;1A,2B,3D,4A

Glossary

cytoplasm（細(xì)）胞質(zhì)

The living contents of a cell bounded externally by the plasmalemma, including an aqueous ground substance(hyaloplasm, cell sap, or cell matrix)containing organelles and various inclusions but excluding the nucleus and visible vacuoles.cytoskeleton

細(xì)胞骨架

Of eukaryotic cells, an internal “skeleton”.Its microtubules and other components structurally support the cell, organize and move its inteftial components.The cytoskeleton also helps free-living cells move through their environment.nucleus

細(xì)胞核，核(復(fù)數(shù) nuclei)The organelle of the eukaryote cell that contains

the

chromosomes and hence ultimately controls cellular activity and inheritance through the activity of the genetic material, DNA chromosome 染色體

A DNA-histone thread residing in the nucleus of a cell.Each chromosome possesses two telomeres and a centromere, and some contain a nucleolus organizer.RNA proteins are invariably associated with the chromosome.nucleoid

擬核，類核，核質(zhì)體

The DNA-containing area of a prokaryote cell, analogous to the eukaryote nucleus but not membrane bounded.nucleoli

核仁(單數(shù)nucleolus)

Nuclear structures composed of completed or partially completed ribosomes and the specific parts of chromosomes that contain the infon-nation for their construction.nuclear envelope

核膜，核被膜

A double membrane(two lipid bilayers and associated proteins)that is the outermost portion of a cell nucleus.ribosome

核糖體

Small structures composed of two protein and ribonucleic acid subunits involved in the assembly of proteins from amino acids.polysome多核糖體

Of protein synthesis, several ribosomes all translating the same messenger RNA molecule,one after the other.endoplasmic reticulum

內(nèi)質(zhì)網(wǎng)

Folded membranes and tubes throughout the eukaryotic cell that provide a large surface upon which chemical activities take place.Golgi complex

高爾基復(fù)合體

A stack of flattened, smooth, membranous sacs;the site of synthesis and packaging of certain molecules in eukaryotic cells.vacuole

液泡

Storage container within the cytoplasm of a cell having a surrounding membrane.phagocytosis

吞噬作用 The process by which the cell wraps around a particle and engulfs it.pinocytosis

胞飲作用

The process by which a cell engulfs some molecules dissolved in water lysosome

溶酶體

A specialized organelle that holds a mixture of hydrolytic enzymes.mitochondrion

線粒體(復(fù)數(shù) mitochondria)A membranous organelle resembling a small bag with a larger bag resembling a small bag with a larger bag inside that is folded back on itself;serves as the site of aerobic cellular respiration.plastid

質(zhì)體

An organelle present in all plants except bacteria, blue-green algae, and fungi;it is enclosed by two membranes(the envelope)and has various functions chloroplast

葉綠體

A plastid in which photosynthesis is carried out.Chloroplasts occur in all photosynthetic organisms except photosynthetic bacteria blue-green algae.stroma基質(zhì)，子座（復(fù)數(shù)stromata）

Region within a chloroplast that has no chlorophyll.microfilament

微絲，纖絲

Long, fiberlike structures made of protein and found in cells, often in close association with the microtubules;provide structural support and enable movement.actin 肌動(dòng)蛋白

A globular contractile protein.In muscle cells, actin interacts with another protein, myosin, to bring about contraction.myosin ['maiesin]

肌球蛋白

A protein that, with actin, constitutes the principal element of the contractile apparatus of muscle.microtubute微管

Small, hollow tubes of protein that function throughout the cytoplasm to provide structural support and enable movement.tubulin

微管蛋白

A protein that is the major constituent of microtubules.dynein

動(dòng)力蛋白，動(dòng)素

A group of at least four distinct proteins found in the flagella and microtubules of eukaryotic cells and possessing ATPase activity.chemotaxis趨化性

A locomotory movement of an organism or cell in response to, and directed by, an directional stimulus.cilia

纖毛

Numerous short, hairlike structures projecting from the cell surface that enable locomotion.flagella

鞭毛(單數(shù)flagellum)

Long, hairlike structures projecting from the cell surface that enable locomotion.basal body 基體

A body identical in structure to a centriole, found always at the base of a cilium or eukaryote flagellum.centriole 中心粒

An organelle located close to the nucleus in most animal and lower plant cells but absent from prokaryotes and higher plants.Lesson Two（2學(xué)時(shí)）

Photosynthesis

教學(xué)目的：使學(xué)生掌握細(xì)胞的光合作用機(jī)理，光合系統(tǒng)Ⅰ與光合系統(tǒng)Ⅱ結(jié)構(gòu)與功能之間的關(guān)系。相關(guān)英語(yǔ)詞匯以及主要用法。

教學(xué)重點(diǎn)：光合作用中相關(guān)的概念和功能，及相關(guān)英語(yǔ)詞匯的掌握 教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：4月5日 教學(xué)內(nèi)容：

Photosynthesis occurs only in the chlorophyll-containing cells of green plants, algae, and certain protists and bacteria.Overall, it is a process that converts light energy into chemical energy that is stored in the molecular bonds.From the point of view of chemistry and energetics, it is the opposite of cellular respiration.Whereas cellular respiration is highly exergonic and releases energy, photosynthesis requires energy and is highly endergonic.光合作用只發(fā)生在含有葉綠素的綠色植物細(xì)胞，海藻，某些原生動(dòng)物和細(xì)菌之中?？傮w來(lái)說(shuō)，這是一個(gè)將光能轉(zhuǎn)化成化學(xué)能，并將能量貯存在分子鍵中，從化學(xué)和動(dòng)能學(xué)角度來(lái)看，它是細(xì)胞呼吸作用的對(duì)立面。細(xì)胞呼吸作用是高度放能的，光合作用是需要能量并高吸能的過(guò)程。

Photosynthesis starts with CO2 and H2O as raw materials and proceeds through two sets of partial reactions.In the first set, called the light-dependent reactions, water molecules are split(oxidized), 02 is released, and ATP and NADPH are formed.These reactions must take place in the presence of light energy.In the second set, called light-independent reactions, CO2 is reduced(via the addition of H atoms)to carbohydrate.These chemical events rely on the electron carrier NADPH and ATP generated by the first set of reactions.光合作用以二氧化碳和水為原材料并經(jīng)歷兩步化學(xué)反應(yīng)。第一步，稱光反應(yīng)，水分子分解，氧分子釋放，ATP和NADPH形成。此反應(yīng)需要光能的存在。第二步，稱暗反應(yīng)，二氧化碳被還原成碳水化合物，這步反應(yīng)依賴電子載體NADPH以及第一步反應(yīng)產(chǎn)生的ATP。

Both sets of reactions take place in chloroplasts.Most of the enzymes and pigments for the lightdependent reactions are embedded in the thylakoid membrane of chloroplasts.The dark reactions take place in the stroma.兩步反應(yīng)都發(fā)生在葉綠體中。光反應(yīng)需要的大部分酶和色素包埋在葉綠體的類囊體膜上。暗反應(yīng)發(fā)生在基質(zhì)中。

How Light Energy Reaches Photosynthetic Cells（光合細(xì)胞如何吸收光能的）

The energy in light photons in the visible part of the spectrum can be captured by biological molecules to do constructive work.The pigment chlorophyll in plant cells absorbs photons within a particular absorption spectrums statement of the amount of light absorbed by chlorophyll at different wavelengths.When light is absorbed it alters the arrangement of electrons in the absorbing molecule.The added energy of the photon boosts the energy condition of the molecule from a stable state to a less-stable excited state.During the light-dependent reactions of photosynthesis, as the absorbing molecule returns to the ground state, the “excess” excitation energy is transmitted to other molecules and stored as chemical energy.生物分子能捕獲可見(jiàn)光譜中的光能。植物細(xì)胞中葉綠素在不同光波下吸收部分吸收光譜。在吸收分子中，光的作用使分子中的電子發(fā)生重排。光子的能量激活了分子的能量狀態(tài)，使其從穩(wěn)定態(tài)進(jìn)入不穩(wěn)定的激活態(tài)。All photosynthetic organisms contain various classes of chlorophylls and one or more carotenoid(accessory)pigments that also contribute to photosynthesis.Groups of pigment molecules called antenna complexes are present on thylakoids.Light striking any one of the pigment molecules is funneled to a special chlorophyll a molecule, termed a reaction-center chlorophyll, which directly participates in photosynthesis.Most photosynthetic organisms possess two types of reaction-center chlorophylls, P680 and P700, each associated with an electron acceptor molecule and an electron donor.These aggregations are known respectively as photosystem Ⅰ(P700)and photosystem Ⅱ(P680).所有的光合作用生物含有不同等級(jí)的葉綠素和一個(gè)或多個(gè)類胡蘿卜素（光合作用的輔助色素）。稱作天線復(fù)合體的色素分子群存在于類囊體中。激活色素分子的光能進(jìn)入葉綠素反應(yīng)中心，其直接參與光合作用。大部分光反應(yīng)細(xì)胞器擁有兩套反應(yīng)中心，P680和P700，每個(gè)光系統(tǒng)都含有一個(gè)電子受體和電子供體。這些集合體就是大家熟識(shí)的光合系統(tǒng)Ⅰ和光合系統(tǒng)Ⅱ。

The Light-Dependent Reaction: Converting Solar Energy into Chemical-Bond Energy 光反應(yīng)：光能轉(zhuǎn)化成化學(xué)鍵能

The photosystems of the light-dependent reactions are responsible for the packaging of light energy in the chemical compounds ATP and NADPH.This packaging takes place through a series of oxidation reduction reactions set in motion when light strikes the P680 reaction center in photosystem Ⅱ.In this initial event water molecules are cleaved, oxygen is released, and electrons are donated.These electrons are accepted first by plastoquinone and then by a series of carriers as they descend an electron transport chain.For each four electrons that pass down the chain, two ATPs are formed.The last acceptor in the chain is the P700 reaction center of photosystem Ⅰ.At this point incoming photons boost the energy of the electrons, and they are accepted by ferredoxin.Ferredoxin is then reoxidized, and the coenzyme NADP+ is reduced to the NADPH.The ATP generated previously and the NADPH then take part in the light independent reactions.光反應(yīng)的光系統(tǒng)將光能轉(zhuǎn)化成化學(xué)復(fù)合物ATP和NADPH。當(dāng)光激活光系統(tǒng)Ⅱ的光反應(yīng)中心時(shí)，通過(guò)一系列的氧化還原反應(yīng)實(shí)現(xiàn)能量的傳遞。反應(yīng)開(kāi)始時(shí)，水被分解，氧被釋放并提供電子。電子首先傳遞給質(zhì)體醌，然后通過(guò)一系列載體形成的電子傳遞鏈。每傳遞4個(gè)電子，形成2個(gè)ATP。最后一個(gè)受體存在于光反應(yīng)系統(tǒng)Ⅰ的反應(yīng)中心里。此處光子激活電子，電子傳遞給鐵氧還蛋白。鐵氧還蛋白再氧化，并且輔酶NADP+還原成NADPH。早期產(chǎn)生的ATP和NADPH進(jìn)入暗反應(yīng)。

The production of ATP from the transport of electrons excited by light energy down an electron transport chain is termed photophosphorylation.The one-way flow of electrons through photosystems II and I is called noncyclic photophosphorylation;plants also derive additional ATP through cyclic photophosphorylation, in which some electrons are shunted back through the electron transport chain between photosystems Ⅱ and Ⅰ.由電子傳遞鏈偶連產(chǎn)生ATP的過(guò)程稱為光合磷酸化。通過(guò)光合系統(tǒng)Ⅱ流經(jīng)光合系統(tǒng)Ⅰ的電子路徑稱非循環(huán)式光合磷酸化；植物通過(guò)循環(huán)式光合磷酸化獲得額外的ATP，一些電子在光合系統(tǒng)Ⅰ和Ⅱ之間的電子傳遞鏈中回流。

The Light-Independent Reactions: Building Carbohydrates 暗反應(yīng)：碳水化合物的形成

In the light-independent reactions of photosynthesis, which are driven by ATP and NADPH, C02 is converted to carbohydrate.The reactions are also known as the Calvin-Benson cycle.Atmospheric CO2, is fixed as it reacts with ribulosebiphosphate(RuBP), a reaction that is catalyzed by the enzyme ribulosebiphosphate carboxylase.The reduction Of C02 to carbohydrate(fructose diphosphate)is completed via several more steps of the cycle.Finally, RUBP is regenerated so that the cycle may continue.由ATP和NADPH驅(qū)動(dòng)的暗反應(yīng)中，二氧化碳轉(zhuǎn)化成碳水化合物。即卡爾文循環(huán)。二磷酸核酮糖固定二氧化碳，由二磷酸核酮糖羧化酶催化。

Oxygen: An Inhibitor of photosynthesis（氧：光合作用的抑制因子）High levels of oxygen in plant cells can disrupt photosynthesis and can also cause photorespiration-an inefficient fun of the dark reactions in which 02 is fixed rather than C02 and no carbohydrate is produced.Reprieve from Photorespiration: The C4 Pathway Most plants are C3 plants;they experience decreased carbohydrate production under hot, dry conditions as a result of the effects of photorespiration.Among C4 plants, however, special leaf anatomy and a unique biochemical pathway enable the plant to thrive in and conditions.Thus C4 plants lessen photorespiration by carrying out photosynthesis only in cells that are insulated from high levels of CO2.They also possess a novel mechanism for carbon fixation.大部分植物是碳3植物，在高溫干旱條件下，由于光呼吸作用而使碳水化合物的合成降低。而在大多數(shù)的碳4植物中，由于葉脈的特殊構(gòu)造和獨(dú)特的化學(xué)路徑使植物依然很茂盛。這是碳固定的一個(gè)新機(jī)制。

課后作業(yè)：第一篇閱讀材料 答案：1B,2A,3A,4D,5C,6c Glossary

light-dependent reactions 光反應(yīng)-The first stage in photosynthesis, driven by light energy.Electrons that trap the sun's energy pass the energy to high-energy carriers such as ATP or NADPH, where it is stored in chemical bonds.light-independent reactions 暗反應(yīng)

The second stage of photosynthesis, also called the Calvin-Benson cycle, which does not require light.During the six steps of the cycle, carbon is fixed and carbohydrates are formed.chloroplast 葉綠體

A plastid in which photosynthesis is carried out.Chloroplasts occur in all photosynthetic organisms except photosynthetic bacteria and blue-green algae.absorption spectrum 吸收光譜，吸收譜

The spectrum obtained when radiation(light, ultraviolet radiation, etc.)from a source giving a continuous spectrum is passed through a substance.Calvin-Benson cycle 卡爾文?本森循環(huán)

Cyclic reactions that are the “synthesis” part of the light-independent reactions of photosynthesis.In land plants, RUBP, or some other compound to which carbon has

been affixed, under goes rearrangements that lead to formation of a sugar phosphate and to regeneration of the RUBP.The cycle runs on ATP and NADPH from light-dependent reactions.carotenoid 類胡蘿卜素

Light-sensitive, accessory pigments that transfer absorbed energy to chlorophylls.They absorb violet and blue wave-lengths but transmit red, orange, and yellow.chlorophyll 葉綠素

The green substance of plants by which photosynthesis is accomplished;it is usually localized in intracellular organelles called chloroplasts.cyclic photophosphorylation 環(huán)形光合磷酸化（作用）

Cyclic photophosphorylation is coupled to cyclicelectron flow, in which ATP is the only product.C3 plant 三碳植物 A plant in which the light-independent reactions of photosynthesis start with a threecarbon compound.Most plants are C3 plants.C4 plant 四碳植物

A plant such as corn in which the light independent reactions of photosynthesis star with a four-carbon compound.noncyclic photophosphorylation

非環(huán)形光合磷酸化作用

Noncyclic photophosphorylation is coupled to noncyclic electron flow, the electrons being used to reduce NADP+ as well as to make ATP.photon 光子

A particle that has zero mass or charge and unit spin, the quantum of the electromagnetic field and carrier of the electromagnetic force.photophosphorylation 光合磷酸化作用

The synthesis of ATP from phosphate and ADP during photosynthesis, using light energy.photorespiration 光呼吸

A light-dependent type of respiration that occurs in most photosynthetic plants and differs from normal(or dark)respiration.photosynthesis 光合作用

The synthesis of organic compounds by reduction of carbon dioxide using light energy absorbed by chorophyll.photosystem 光合系統(tǒng)

One of the clusters of light-trapping pigments embedded in photosynthetic membranes.Photosystem I operates during the cyclic pathway;photosystem Ⅱ operates during both the cyclic and noncyclic pathways.ribulosebiphosphate(RUBP)核酮糖二磷酸

A compound with a backbone of five carbon atoms that is required for carbon fixation in the Calvin-Benson cycle of photosynthesis.thylakoid 類囊體

One of a number of flattened fluid-filled sacs that form the photosynthetic lamellar system of chloroplasts, photosynthetic bacteria, and blue-green algae.Lesson Three（2學(xué)時(shí)）

Cellular Reproduction: Mitosis and Meiosis

教學(xué)目的：使學(xué)生掌握細(xì)胞的有絲分裂和無(wú)絲分裂的作用機(jī)理，有絲分裂和無(wú)絲分裂之間的區(qū)別和相同點(diǎn)。相關(guān)英語(yǔ)詞匯以及主要用法。

教學(xué)重點(diǎn)：有絲分裂和無(wú)絲分裂中相關(guān)的概念和功能，及相關(guān)英語(yǔ)詞匯的掌握 教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：4月12日 教學(xué)內(nèi)容：

The Nucleus and Chromosomes The cell nucleus is the main repository of genetic information.Within the nucleus are the chromosomes tightly coiled strands of DNA and clusters of associated proteins.Long stretches of the continuous DNA molecule wind around these clusters of proteins, or histones, forming beadlike complexes known as nucleosomes.More coiling and supercoiling produces a dense chromosome structure.Each long strand of DNA combines with histones and nonhistone proteins to make up the substance chromatin.細(xì)胞核是貯藏遺傳信息的主要場(chǎng)所。DNA盤(pán)繞成螺旋線以及相關(guān)的成簇蛋白質(zhì)。DNA螺旋線纏繞成簇的組蛋白形成珠鏈狀的核小體。這些螺旋和超螺旋形成致密的染色體組結(jié)構(gòu)。每個(gè)長(zhǎng)鏈DNA與組蛋白和非組蛋白一起構(gòu)成染色質(zhì)物質(zhì)。

A pictorial display of an organism's chromosomes in the coiled, condensed state is known as a karyotype.Karyotype reveal that in most cells all but sex chromosomes are present as two copies, referred to as homologous pairs.Non-sex chromosomes are called autosomes.Organisms whose cells contain two sets of parental chromosomes are called diploid;those with cells containing a single set of parental chromosomes are called haploid.染色體致密的超螺旋狀態(tài)我們稱染色體組。除了性染色體外，大多數(shù)細(xì)胞的染色體組成對(duì)出現(xiàn)，稱同源染色體對(duì)。非性染色體稱常染色體。生物細(xì)胞含有兩套父母本染色體的稱二倍體；含有單套染色體的稱單倍體。

The Cell Cycle The cell cycle is a regular sequence in which the cell grows, prepares for division, and divides to form two daughter cells, each of which then repeats the cycle.Such cycling in effect makes single-celled organisms immortal.Many cells in multicellular organisms, including animal muscle and nerve cells, either slow the cycle or break out of it altogether.在細(xì)胞生長(zhǎng)過(guò)程中，細(xì)胞循環(huán)遵循特定程序，分裂準(zhǔn)備，分裂成2個(gè)子細(xì)胞，子細(xì)胞再循環(huán)。此循環(huán)使得單細(xì)胞永生。多細(xì)胞生物中的許多細(xì)胞，包括動(dòng)物肌肉和神經(jīng)細(xì)胞，要么降低循環(huán)速度，要么同時(shí)分裂。The normal cell cycle consists of four phases.The first three include G1, the period of normal metabolism;S phase, during which normal synthesis of biological molecules continues, DNA is replicated, and histones are synthesized;and G2, a brief period of metabolism and additional growth.Together the G1, S, and G2 phases are called interphase.The fourth phase of the cell cycle is M phase, the period of mitosis, during which the replicated chromosomes condense and move and the cell divides.It is believed that properties of the cell cytoplasm control the cell cycle, along with external stimulators and inhibitors such as chalones.正常細(xì)胞循環(huán)由4個(gè)時(shí)期組成。頭三期包括G1,正常新陳代謝；S期,正常新陳代謝同時(shí)，DNA復(fù)制，組蛋白合成； G2 期，短期的新陳代謝和少許生長(zhǎng)。G1, S, 和G2稱分裂間期。最后是M期，有絲分裂期，復(fù)制的染色體組濃縮，移動(dòng)并細(xì)胞分裂。據(jù)稱是染色質(zhì)控制了細(xì)胞循環(huán)，伴隨外部激活因子和抑制因子如抑素。

Mitosis: Partitioning the Hereditary Material Biologists divide the mitotic cycle into four phases.At the beginning of prophase the chromosomes each consist of two highly condensed chromatids attached to each other at a centromere.As prophase ends and metaphase begins, the condensed chromosomes become associated with the spindle.Eventually the chromosomes become arranged in a plane(called the metaphase plate)at a right angle to the spindle fibers.Next, during anaphase, the two sister chromatids of each chromosome split, and one from each pair is drawn toward each pole of the cell.During telophase nuclear envelopes begin to form around each set of chromosomes, and division of the cytoplasm takes place.生物學(xué)家將有絲分裂劃分為4個(gè)階段。分裂前期，高度濃縮的兩個(gè)染色單體通過(guò)著絲粒連接在一起。在分裂前期后期和分裂中期前期，濃縮的染色體與紡錘體相連，最后以正確的角度排列在赤道板上。在分裂后期，兩個(gè)姊妹單體分離，分別拽向細(xì)胞兩極。在分裂末期，在每套染色體周?chē)纬珊四?，?xì)胞質(zhì)發(fā)生分裂。As mitosis proceeds, the spindle microtubules play a crucial role in ensuring that both paired and separated chromatids move in the right directions at the proper times.Each half of the spindle forms as microtubules extend from each pole of a dividing cell to the region of the metaphase plate.During prophase, other microtubules, the centromeric fibers, extend outward from the spindle poles to structures on the chromosomes called kinetochores.During anaphase the fibers begin to shorten, and the chromatids begin to move apart.在有絲分裂過(guò)程中，是紡錘體微管確保了染色單體在適當(dāng)時(shí)間以正確方向進(jìn)行分離。紡錘體微管由兩極向赤道板延伸。在分裂前期，其它微管，著絲粒纖維延伸到染色體的動(dòng)粒。在分裂后期，纖維開(kāi)始變短，染色單體分離。

The spindle forms differently in plant and animal cells.In animals it is associated with centriole, while in plant and fungal cells spindle formation is associated with reions called microtubule organizing centers.植物和動(dòng)物細(xì)胞形成的紡錘體不同。動(dòng)物細(xì)胞與中心粒相連，而在植物和真菌細(xì)胞中，紡錘體與微管組織中心的離子相連。

Cytokinesis: Partitioning the Cytoplasm 胞質(zhì)分裂：細(xì)胞質(zhì)分離

The division of the cell cytoplasm at the end of mitosis is called cytokinesis.In animal cells it takes place as a ring of actin filaments contracts around the cell equator, pinching the cell in two.In plant cells, which are bounded by a cell wall, cytokinesis involves the building of a new cell plate across the dividing cell at its equator.Cell wall material is then deposited in the region of the cell plate.在動(dòng)物細(xì)胞中，環(huán)形肌動(dòng)蛋白絲延赤道板收縮而使細(xì)胞一分為二。在植物細(xì)胞中，在赤道板形成新的細(xì)胞板。

Meiosis: The Basis of Sexual Reproduction Meiosis is a special form of cell division that takes place in the reproductive organs that produce sex cells.Like mitosis, it takes place after DNA replication has occurred and involves two sequential nuclear divisions(meiosis I and meiosis Ⅱ).These divisions result in four daughter cells, each with half the number of chromosomes of the parent cell.The phenomenon of crossing over during meiosis results in exchanges of genetic information between chromosomes.Hence, the homologous chromosomes distributed to different progeny cells are not identical.減數(shù)分裂是性細(xì)胞分裂的特殊形式。如有絲分裂，它也是發(fā)生在DNA復(fù)制后并有連續(xù)的兩個(gè)核分裂。產(chǎn)生4個(gè)子細(xì)胞，分別含有親本一半的染色體數(shù)。

As in mitosis two chromatids exist for each chromosome at the beginning of prophase 1.During this phase the homologous chromosomes undergo synapsis, or pairing, which is brought about by a bridging structure of proteins and RNA called the synaptonemal complex.The homologous pairs stay together when they align on the metaphase plate.Unlike the anaphase of mitosis, however, during anaphase I the two chromatids of each chromosome stay joined at the centromere and move together to one of the two poles of the cell.It is this event that results in the halving of the chromosome number in the four daughter cells that result from meiosis.正如在有絲分裂中一樣，兩個(gè)同源染色單體通過(guò)蛋白質(zhì)和RNA橋配對(duì)形成聯(lián)會(huì)復(fù)合體。與有絲分裂不同的是，每組染色體的兩個(gè)染色單體連接在著絲點(diǎn)上并一起移向細(xì)胞兩極的一級(jí)。由此而導(dǎo)致4個(gè)子細(xì)胞染色體數(shù)減半。

During telophase I nuclear envelopes enclose the chromosomes in nuclei, and in most species cytokinesis(the first nuclear division)follows.The second nuclear division begins with metaphase Ⅱ, in which the chromosomes in each daughter cell again align on a metaphase plate.The centromeres finally divide, and each sister chromatid moves to one of the poles of the spindle.The next phase is telophase , followed again by cytokinesis.The result of the entire process is four haploid cells in which parental chromosomes are randomly distributed.第二次核分裂開(kāi)始于分裂中期，子細(xì)胞中染色體重新排列在赤道板上。著絲粒最終分離，每個(gè)姊妹染色單體分向兩極。接著胞質(zhì)分裂。產(chǎn)生4個(gè)單倍體，父母染色體隨機(jī)分配。Asexual Versus Sexual Reproduction Mitosis and meiosis, respectively, make simple cell division and sexual reproduction possible.Each means of passing on hereditary information has advantages.In asexual reproduction the parent organism gives rise to offspring that are genetic clones of the parent.The advantages of this type of reproduction are that it preserves the parent's successful genetic complement, requires little or no specialization of reproductive organs, and is more rapid than sexual reproduction.A major disadvantage of the asexual mode is that a single catastrophic event or disease may destroy an entire population of genetically identical organisms.A prime benefit of sexual reproduction is that it provides genetic variability and a ready mechanism for the elimination of deleterious mutations.It also allows “new” gene forms to arise and spread through populations.有絲分裂和減數(shù)分裂在傳遞遺傳信息過(guò)程中各有優(yōu)勢(shì)。體細(xì)胞的繁殖就是父母本的克隆，其優(yōu)勢(shì)是保留了父母本的成功遺傳信息，不需要特殊器官，比性復(fù)制快的多。但一個(gè)簡(jiǎn)單災(zāi)難性事件或疾病都可能摧毀一個(gè)細(xì)胞群體。性復(fù)制的優(yōu)勢(shì)是它提供了遺傳可變性和現(xiàn)存排除有害突變的機(jī)制。也可以產(chǎn)生新的基因并在種群中蔓延。

課后作業(yè)：第一篇閱讀材料 答案：1C,2B,3D,4B,5A,6D

Glossary

mitosis 有絲分裂

Process that results in equal and identical distribution of replicated chromosomes into two newly formed nuclei.meiosis 減數(shù)分裂

The process by which a nucleus divides into four daughter nuclei, each containing half the number of chromosomes of the parent nucleus.histone 組蛋白

One of a group of simple proteins that have a high content of the basic amino acids arginine or lysine and are found associated with nucleic acids in the chromatin of eukaryotic cells.nucleosome 核小體

The basic unit of chromatin structure in eukaryotic cells.A nucleosome consists of eight histone molecules of four different types, together with about 140 base pairs of DNA coiled around it.chromatin 染色質(zhì)

The material of which the chromosomes are composed.DNA and protein are the main constituents of chromatin, most of the protein being histone.karyotype 核型，染色體組型 , The appearance of the chromosome complement of an organism or cell.homologous pair 同源染色體對(duì)

Chromosomes that pair during meiosis.Each homologue is a duplicate of one of the chromosomes contributed at syngamy by the mother or father.Homologous chromosomes contain the same linear sequence of genes and as a consequence each gene is present in duplicate.diploid二倍體

Any nucleus, cell, or organism that possesses twice the haploid number of chromosomes.haploid 單倍體 Any nucleus, cell, or organism that possesses a single set of unpaired chromosomes, interphase(cycle)分裂間期（周期）

In a cell preparing to duplicate, the interphase stage can divided into a period of initial growth(G1), a period of DNA synthesis(S), and a second growth period(G2).chalone抑素

Substances found in mammalian tissue homogenates that, when applied to intact tissue cells, inhibit mitosis, particularly in the presence of adrenaline and corticosteroids.prophase（分裂）前期

First stage of mitosis, during which individual chromosomes become visible.chromatid 染色單體

A replicated chromosome physically attached to an identical chromatid at the centromere.centromere 著絲粒

The small area of a chromosome that does not stain with basic dyes during mitosis and meiosis;at interphase it is single while the rest of the chromosome is made up of two chromatids.metaphase（分裂）中期

Second stage in mitosis, during which the chromosomes align at the equatorial plane.spindle 紡錘體

An array of microtubutes extending from pole to pole and used in the movement of chromosomes.metaphase plate 赤道板，中期板

The grouping of the chromosomes in a plane at the equator of the spindle during the metaphase stage of mitosis.anaphase 分裂后期

The third stage of mitosis, during which the centromeres split and the chromosomes move to the poles.telophase（分裂）末期

Last stage in mitosis during which daughter nuclei are formed.cytokinesis 胞質(zhì)分裂

Division of the cytoplasm of one cell into two new cells.cell plate 細(xì)胞板

A plant cell structure that begins to form in the center of the cell and proceeds to the cell membrane, resulting in cytokinesis.Lesson Four（2學(xué)時(shí)）

Foundations of Genetics

教學(xué)目的：使學(xué)生了解遺傳學(xué)的發(fā)展歷程，掌握孟德?tīng)栠z傳學(xué)的建立及經(jīng)典實(shí)驗(yàn)。相關(guān)英語(yǔ)詞匯以及主要用法。教學(xué)重點(diǎn)：孟德?tīng)栠z傳學(xué)的兩個(gè)定律，及相關(guān)英語(yǔ)詞匯的掌握 教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：4月19日 教學(xué)內(nèi)容：

Early Theories of inheritanee Early ideas of inheritance included Hippocrates' theory of pangenesis and August Weismands germ plasm theory.Based on experiments with mice, Weismann proposed that hereditary information in gametes transmitted traits to progeny.Both of these early views incorporated the blending theory: they held that heritable traits of the two parents blend, so that the distinct characteristics of each are lost in offspring.遺傳學(xué)的早期理論包括泛生說(shuō)和種質(zhì)理論?；谛∈髮?shí)驗(yàn)，維絲曼提出遺傳信息儲(chǔ)存在配子中并將遺傳信息傳遞給后代。這兩個(gè)早期觀點(diǎn)合起來(lái)形成融合理論：子代擁有父母本混合的遺傳特征，而不完全象親代。Gregor Mendel and the Birth of Genetics Gregor Mendel, an Augustinian monk in the monastery at Brunn, Austria, is known as the “father of genetics.” Having been exposed to theories of the particulate nature of matter while a university student and having a background in mathematics, Mendel carried out a series of carefully planned experiments that demonstrated the particulate nature of heredity.His revolutionary ideas were neither understood nor accepted until many years after Mendel died.孟德?tīng)?，眾所周知的遺傳學(xué)之父，是一名修道士。當(dāng)他還是大學(xué)生時(shí)就提出了物質(zhì)的粒子屬性。孟德?tīng)栠M(jìn)行了一系列周密安排的實(shí)驗(yàn)來(lái)證實(shí)遺傳的顆粒性。直到他去世后，他的理論才被理解和接受。Mendel's Classic Experiments Mendel studied genetics through plant-breeding experiments with the garden pea, a plant species that is self-fertilizing and h offspring is identical to the parent in the trait of interest).To test the blending theory, he focused his research on seven distinct characters.Each of these characters, such as seed color and plant height, present only two, clear-cut possibilities.He also recorded the type and number of all progeny produced from each pair of parent pea plants, and followed the results of each cross for two generations.孟德?tīng)柾ㄟ^(guò)豌豆實(shí)驗(yàn)研究遺傳學(xué)，豌豆是自花授粉植物和純品系。為驗(yàn)證融合理論，他的研究主要集中在7個(gè)特征上。例如，種子顏色，植株高度，這些特征只有兩個(gè)明確的可能性。他記錄了產(chǎn)生的每一個(gè)子代類型和數(shù)量，在雜交產(chǎn)生子2代。

For each of the characters he studied, Mendel found that one trait was dominant while the other was recessive.In the second filial(F2)generation, the ratio of dominant to recessive was 3:1.Mendel deduced that this result was possible only if each individual possesses only two hereditary units, one from each parent.The units Mendel hypothesized are today known as alleles, alternative forms of genes.Genes are the basic units of heredity.An organism that inherits identical alleles for a trait from each parent is said to be homozygous for that trait;if different alleles for a trait are inherited, the organism is heterozygous for that trait.When an organism is heterozygous for a trait, the resulting phenotype for that trait expresses only the dominant allele.Thus, the organism’s phenotype—its physical appearance and properties-differs from its genotype, which may include both a dominant and a recessive allele.A pictorial representation of all possible combinations of a genetic cross is known as a Punnett square.對(duì)于每個(gè)特征而言，要么顯形，要么隱性。在子2代中顯形與隱性比為3∶1。只有在每個(gè)個(gè)體僅擁有兩個(gè)研究遺傳單元，并每個(gè)單元來(lái)自一個(gè)親代時(shí)，實(shí)驗(yàn)結(jié)果才成立。此遺傳單元就是今天共識(shí)的等位基因。兩個(gè)一樣的等位基因決定一個(gè)特征，稱純合。相反，稱雜合。當(dāng)生物是雜合時(shí)，它的表型由顯性基因決定。因此，生物的表型與基因型是不同的。旁納特方格可以陳列所有可能的遺傳組合。The results of Mendel's experiments on dominant and recessive inheritance let to Mendel's first law: the law of segregation.This law states that for a given trait an organism inherits one allele from each parent.Together these alleles form the allele pair.When gametes are formed during meiosis, the two alleles become separated(halving of chromosome number).To gain evidence for his theory Mendel performed test crosses, mating plants of unknown genotype to plants that were homozygous recessive for the trait of interest.The ratio of dominant phenotypes(if any)in the progeny makes clear whether the unknown genotype is heterozygous, homozygous dominant, or homozygous recessive.分離定律，生物只遺傳父母本等位基因?qū)Φ囊粋€(gè)等位基因。減數(shù)分裂期形成配子時(shí)兩個(gè)等位基因分離。為驗(yàn)證此理論，他做了測(cè)交實(shí)驗(yàn)，即基因型未知的植物與純合的隱性基因植物雜交。子代顯性表型可以明確測(cè)得雜合基因或純合基因的基因型。

Mendel's Ideas and the Law of independent Assortment Mendel also performed dihybrid crosses, which enabled him to consider how two traits are inherited relative to one another.This work let to the law of independent assortment, which states that the alleles of genes governing different characters are inherited independently.An apparent exception to Mendel's laws is incomplete dominance, a phenomenon in which offspring of a cross exhibit a phenotype that is intermediate between those of the parents.However, incomplete dominance reflects the fact that both alleles for the trait in question exert an effect on the phenotype.The alleles themselves remain separate.雙因子雜合試驗(yàn)，兩個(gè)特征是如何相互影響遺傳的。試驗(yàn)結(jié)果產(chǎn)生獨(dú)自分配定律，即等位基因獨(dú)立遺傳。特例是，不完全顯性。子代的表型是父母本的中間類型。不完全顯性說(shuō)明了兩個(gè)等位基因?qū)Ρ硇投加杏绊?。，等位基因?huì)繼續(xù)分離。

Mendel presented his ideas in 1866 in a scientific paper published by the Brunn Society for Natural History.Unfortunately, the meaning of his research was not understood by other scientists of the day.His work was rediscovered in 1900 by Carl Correns and Hugo de Vries.1866年，孟德?tīng)栐谧匀皇飞习l(fā)表了他的科學(xué)論文，陳訴了他的觀點(diǎn)。不幸的是，他的研究不被當(dāng)時(shí)科學(xué)家接受。在1900年，他的著作再被發(fā)現(xiàn)利用。Chromosomes and Mendelian Genetics Soon after Mendel's work was rediscovered, Walter Sutton and Theodor Boveri independently proposed that the hereditary units might be located on chromosomes.Experiments to prove this hypothesis were carried out by Thomas Hunt Morgan and his students at Columbia University, in research on the sex chromosomes of fruit flies.Morgan's studies were also the first exploration of sex-linked traits.It also led to the discovery in 1916 by Calvin Bridges of the phenomenon of nondisjunction, in which a chromosome pair fails to segregate during meiosis.孟德?tīng)栔鞅辉侔l(fā)現(xiàn)不久，Walter Sutton 和Theodor Boveri提出，遺傳單位可能定位在染色體組上。伴性遺傳又導(dǎo)致了不分離現(xiàn)象的發(fā)現(xiàn)，即在減數(shù)分裂中，染色體對(duì)不分離。課后作業(yè)：第一篇閱讀材料 答案：1C,2C,3A,4A,5B,6B Glossary

pangenesis 泛生論，泛生說(shuō)

The theory of heredity postulating that germs, humours, or essences migrate from individual body cells to the sex organs and contribute to the gametes.germ plasm theory 種質(zhì)學(xué)說(shuō)

A substance thought to be transmitted in the gametes(germ cells)in an unchanged form from generation to generation.The germ plasm was believed to be unaffected by the environment and to give rise to the body cells.dominant 顯性

The member of a pair of alleles that shows its effect in the phenotype whatever other allele is present.recessive 隱形的

The member of a pair of alleles that does not show its effect in the presence of any other allelic partner.allele 等位基因

Alternative forms of a gene for a particular characteristic(e.g., attached earlobe genes and free earlobe genes are alternative alleles for ear shape).gene 基因

A unit of heredity located on a chromosome and composed a sequence of DNA nucleotides.homozygous 純合的

A diploid organism that has two identical alleles for particular characteristic.heterozygous 雜合的

A diploid organism that has two different alletic forms of a particular gene.Genotype 基因型 The catalog of genes of an organism, whether or not these genes are expressed.phenotype 表型

The physical, chemical, and psychological expression of genes possessed by an organism.Punnett square 旁納特方格

A method used to determine the probabilities of combination in a zygote.law of segregation 分裂定律

When gametes are formed by a diploid organism, the alleles that control a trait separate from one another into different gametes, retaining their individuality.test cross 測(cè)交

A cross between a heterozygote of unknown genotype and an individual homozygous for the recessive genes in question.dihybrid cross 雙因子雜種，雙因子雜合子

A cross between individuals that differ with respect to two specified gene pairs.law of independent assortment 獨(dú)立分配定律，自由組合定律

Members of one gene pair will separate from each other independently of the members of other gene pairs.incomplete dominance 不完全顯性

The condition in which two allelic genes have a different effect when they are together as a heterozygote in a diploid cell than either of them have in the homozygous state nondisjunction 不分離

The failure of separation of paired chromosomes at metaphase, resulting in one daughter receiving both and the other daughter cell none of the chromosomes in question.Nondisjunction can occur during a meiotic or mitotic division.Lesson Five（2學(xué)時(shí)）

Discovering the Chemical Nature of the Gene

教學(xué)目的：使學(xué)生了解遺傳學(xué)化學(xué)本質(zhì)的發(fā)現(xiàn)過(guò)程，及相關(guān)假說(shuō)，使學(xué)生掌握相關(guān)專業(yè)詞匯以及主要用法。教學(xué)重點(diǎn)：DNA分子組成及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：4月26日 教學(xué)內(nèi)容：

Genes Code for Particular Proteins The first scientist to investigate the question of how genes affect phenotype was Sir Archibald Garrod, whose studies of alkaptonuria implied a relationship between genes and enzymes.Thirty years later Beadle and Ephrussi showed a relationship between particular genes and biosynthetic reactions responsible for eye color in fruit flies.Next, in a series of classic experiments on the effects of mutations in the bread mold Neurosporacrassa, Beadle and Tatum explored the one-gene-one-enzyme hypothesis-the idea that each gene codes for a particular enzyme.Their work paved the way for other researchers to elucidate the precise ways in which enzymes affect complex metabolic pathways.In 1949, in research on the role of hemoglobin in sickle cell anemia, Linus Pauling helped refine the one-gene-one-enzyme hypothesis into the one-gene-one-polypeptide hypothesis.Archibald Garrod是第一個(gè)研究基因是如何影響表型的科學(xué)家，他對(duì)尿黑酸癥的研究揭示了基因與酶之間的關(guān)系。Beadle 和Ephrussi在三十年后對(duì)果蠅眼睛顏色的研究發(fā)現(xiàn)特殊基因與相關(guān)反應(yīng)的生物合成有關(guān)。接著對(duì)面包發(fā)霉粗糙脈孢菌的突變?cè)囼?yàn)得出一個(gè)基因一個(gè)酶的假說(shuō)。他們的工作為其他工作者鋪平了道路，即精確地闡明了酶影響了復(fù)雜的新陳代謝途徑。在1949年，對(duì)鐮刀狀細(xì)胞貧血癥的研究對(duì)一個(gè)基因一個(gè)酶的假說(shuō)進(jìn)一步上升為一個(gè)基因一個(gè)多肽。

The Search for the Chemistry and Molecular Structure of nucleic Acids Nuclei acid, originally isolated by Johann Miescher in 1871, was identified as a prime constituent of chromosomes through the use of the red-staining method developed by Feulgen in the early 1900s.Frederick Griffith's experiments with the R and S stains of pneumococci showed that an as yet unknown material from one set of bacterial could alter the physical traits of a second set.In the 1940s the team of Avery, MacLeod, and McCarty showed that this unknown material was DNA.At about the same time P.A.Levene discovered that DNA contained four nitrogenous bases, each of which was attached to a sugar molecule and a phosphate group-a combination Levene termed a nucleotide.在1871年，核酸最初是由Johann Miescher分離成功，并由Feulgen在1900年證實(shí)核酸是染色體組最基本的組成。Frederick Griffith對(duì)粗糙和光滑的肺炎球菌實(shí)驗(yàn)表明，不確定的某種物質(zhì)可以從一組細(xì)菌轉(zhuǎn)移到另一種細(xì)菌中。在1940年，確認(rèn)該物質(zhì)為DNA。四個(gè)堿基和磷酸分子分別連接在糖分子上，稱核苷酸。Disagreement over whether DNA could carry complex genetic information was ended in the early 1950s by Martha Chase and Alfred Hershey, whose work with E.coli showed clearly that DNA, and not protein, is the bearer of genetic information.直到1950年，通過(guò)對(duì)大腸桿菌實(shí)驗(yàn)發(fā)現(xiàn)，遺傳物質(zhì)是DNA，而不是蛋白質(zhì)。

Each DNA nucleotide contains a five-carbon sugar, deoxyribose, attached to one of four bases: adenine, guanine, cytosine, or thymine.Adenine and guanine molecules are double-ring structures called purines, while cytosine and thymine are single-ring structures called pyrimidines.The molecule made up of a base plus a sugar is termed a nucleoside.In each molecule of DNA a phosphate group links the five-carbon sugar of one nucleoside to the five-carbon sugar of the next nucleoside in the chain.This phosphate bonding creates a sugar-phosphate backbone.每個(gè)核苷酸都含有一個(gè)五碳脫氧核糖，分別連接4個(gè)堿基，即：腺嘌呤，鳥(niǎo)嘌呤，胞嘧啶，胸腺嘧啶。堿基連接糖稱核苷。磷酸鍵形成磷酸骨架。

Chargaff’s rules describe the fact that(1)the amount of adenine is equal to the amount of thymine in DNA, with amount of cytosine equal to that of guanine, and(2)the ratios of A to T and of C to G vary with different species.（1）腺嘌呤與胸腺嘧啶，胞嘧啶與鳥(niǎo)嘌呤相等；（2）腺嘌呤與胸腺嘧啶，胞嘧啶與鳥(niǎo)嘌呤的比例隨物種不同而不同。

The Research Race for the Molecular Structure of DNA In the late 1940s and early 1950s, researchers looking for the structure of DNA drew upon Chargaff s insight, Levene's ideas on DNA components, and two other lines of evidence.One was the suggestion of Linus Pauling that DNA might have a helical structure held in place by hydrogen bonds, and the other was X-ray diffraction photos of DNA, showing a helical structure with distance between the coils, taken by Franklin and Wilkins.直到40年代末50年代初，研究者在尋求DNA結(jié)構(gòu)過(guò)程中，確立了Chargaff 的觀點(diǎn)和, Levene的組成理論以及其他兩個(gè)線索。一個(gè)是Linus Pauling的假設(shè)，DNA可能具有螺旋結(jié)構(gòu)，通過(guò)氫鍵連接。另一個(gè)是X-衍射圖片，F(xiàn)ranklin and Wilkins提供。

Based on this information Watson and Crick proposed the double helix model of DNA-A twisted ladder-like molecule with two outer sugar phosphate chains and rungs formed by nucleotide pairs.Paired nucleotides, which always occur as A-T or G-C, are linked by hydrogen bonds.Watson and Crick also proposed that genetic information is encoded by the sequence of base pairs along the DNA molecule.基于這些信息，Watson 和 Crick提出了雙螺旋結(jié)構(gòu)模型，成對(duì)的核苷酸通過(guò)氫鍵相連，遺傳信息就貯藏在堿基對(duì)中。

How DNA Replicates In their model of DNA structure and function, Watson and Crick hypothesized that DNA replicates itself by “unzipping” along the hydrogen bonds joining A to T and C to G.This process would produce two opposite halves that could then serve as templates for the construction of new, complementary strands.This model of semiconservative replication conservative because each new molecule has one half of the former parent molecule-was later confirmed by the work of DNA進(jìn)行復(fù)制是以拉鏈方式自我復(fù)制，產(chǎn)生的兩個(gè)二分體分別為模板生成互補(bǔ)鏈，即半保留復(fù)制。并由Meselson和 Stahl驗(yàn)證。

In E.coli DNA replication begins with the formation of a bubblelike structure on the circular chromosome that is produced by replication forks.Studies of bacterial DNA replication have shown that a growing DNA chain lengthens only in the 5' to 3' direction(from the 5' carbon of one sugar to the 3' carbon of the next).The leading strand is synthesized continuously, while the lagging strand is synthesized in short stretches known as Okazaki fragments.The enzyme DNA polymerase links free nucleotides as they line up on the template formed by the original strand of the parent molecule.In eukaryotes DNA replication follows the same general principles as in prokarotes.On the long DNA molecules replication proceeds(in two directions at once)from hundreds or thousands of points of origin.大腸桿菌復(fù)制開(kāi)始時(shí)形成泡樣復(fù)制叉，鏈生長(zhǎng)方向由5′向3′端，前導(dǎo)鏈連續(xù)生成，后隨鏈由岡崎片段組成，由DNA聚合酶催化。真核生物復(fù)制與原核生物復(fù)制相似，但有幾百到幾千個(gè)復(fù)制原點(diǎn)（原核一般只有一個(gè)復(fù)制原點(diǎn)）。

課后作業(yè)：第一篇閱讀材料 答案：1C,2C,3B,4A,5D,6D,7B

Glossary

one-gene-one-enzyme hypothesis 一基因一酶假說(shuō)

The hypothesis that a large class of gene exist in which each gene controls the synthesis or activity of but a single enzyme.Since enzymes and other proteins whose syntheses are controlled by more than one gene are now known, this hypothesis has been replaced by the one-gene-one polypeptide hypothesis.one-gene-one-polypeptide hypothesis一基因一多肽假說(shuō) The hypothesis that a large class of genes exist in which each gene controls the synthesis of a single polypeptide.The polypeptide may function independently or as a subunit of a more complex protein.adenine 腺嘌呤

A purine base that is an essential constituent of the nucleic acids and also of such coenzymes as NAD and FAD.guanine 鳥(niǎo)嘌呤

A double-ring nitrogenous base molecule in DNA and RNA.It is the complementary base of cytosine.cytosine胞嘧啶

A single-ring nitrogenous base molecule in DNA and RNA.It is complementary to guanine.thymine 胸腺嘧啶

A single-ring nitrogenous base molecule of DNA but not RNA.It is complementary to adenine.purine 嘌呤

One of a group of nitrogenous bases whose parent compound has the formula shown.The two most abundant purines are adenine and guanine, which are constituents of nucleic acids and coenzymes.pyrimidine 嘧啶

A heterocyclic organic compound, C4N4N2 the fundamental form of pyrimidine bases.Some of these bases are constituents of nucleic acid.nucleoside 核苷

A purine or pyrimidine base attached to ribose or deoxyribose.The nucleosides commonly found in DNA and RNA are: cytidine, cytosine deoxyriboside, thymidine, uridine, adenosine, adenine deoxyriboside, guanosine, and guanine deoxyriboside.Note that thymidine is a deoxyriboside and cytidine, uridine, adenosine,andguanosine are ribosides.X-ray diffraction

X射線衍射

A technique for determining the arrangement of atoms in a crystalline substance by analysing the diffraction patterns produced when a narrow beam of X-rays is passed through the substance.X-ray diffraction has contributed to the elucidation of structure of many biological molecules, including some important macromolecules, e.g., DNA, haemoglobin, myoglobin.DNA double helix 雙螺旋

The three-dimensional structure of doublestranded DNA.semiconservative replication 半保留復(fù)制

The method of replication of DNA in which the molecule divides longitudinally, each half being conserved and acting as a template for the formation of a new strand.replication fork 復(fù)制叉

A point at which the two strands of a DNA double helix are unwound and separated during replication.Okazaki fragment 岡琦片斷

A short sequence of DNA that is the primary product of DNA polymerase during DNA replication.polymerase DNA 聚合酶

An enzyme that brings new DNA triphosphate nucleotides into position for bonding on another DNA molecule.Lesson Six（2學(xué)時(shí)）

The Origin and Diversity of Life

教學(xué)目的：使學(xué)生了解生命的起源和多樣性及相關(guān)假說(shuō)，使學(xué)生掌握相關(guān)專業(yè)詞匯以及主要用法。教學(xué)重點(diǎn)：生物分類的組成及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：5月10日 教學(xué)內(nèi)容：

A Home for Life: Formation of the Solar System and Planet Earth The story of life's origins begins with the formation of the earth.The sequence of events that gave rise to our planet began, in turn, with the cosmic explosion physicists call the Big Bang.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.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.Basic physical features of Earth that may have made the emergence of life possible include the planet's size, temperature, composition, and distance from the sun.The major current hypothesis holds that life arose spontaneously on the early earth by means of chemical evolution from nonliving substances.生命起源于地球的形成。大爆炸是我們行星形成的開(kāi)始。太陽(yáng)在50億年前生成，位于太陽(yáng)系中心，行星，包括地球，在46億年前生成。地球由多層組成：堅(jiān)硬的地殼，半流體的地幔，一個(gè)很大的溶解中心中存在一個(gè)堅(jiān)實(shí)的中心。地球的基本特征使生命起源成為可能，包括行星的大小，溫度，組成以及離太陽(yáng)的距離。當(dāng)前主要假設(shè)認(rèn)為，由非生命的化學(xué)物質(zhì)進(jìn)化過(guò)程自發(fā)產(chǎn)生了生命。The Emergence of life: Organic and Biological Molecules on a Primitive Planet Evidence for prelife stages of chemical organization comes from laboratory experiments that try to duplicate the physical environment and chemical resources of the early earth.These experiments, including the pioneering work of Miller and Urey, have successfully produced organic monomers including amino acids, simple sugars, and nucleic acid bases.The probable next step toward life was the spontaneous linking of such monomers into polymers such as proteinoids and nuclei acids.Current research suggests that likely sites for this polymerization were clay or rock surfaces.通過(guò)創(chuàng)造出地球早期的自然條件和化學(xué)資源條件，科學(xué)家在實(shí)驗(yàn)室中已經(jīng)獲得了化學(xué)有機(jī)體生命前階段的證據(jù)。這些實(shí)驗(yàn)包括米勒等早期所做工作，成功地產(chǎn)出了有機(jī)單體，包括氨基酸，單糖，核酸堿基。這些單體自發(fā)的連接成多聚體，如類蛋白和核酸，使進(jìn)入生命狀態(tài)成為可能。這些聚合作用可能發(fā)生在泥土或巖石表面。

Researchers have found that, when energy is available to a system, they can generate three kinds of organic molecular aggregates.The Russian AleksandrOparin obtained polymer-rich droplets, called coacervates from solutions of polymers.Sidney Fox generated proteinoid microspheres from mixtures of amino acids and water.A third laboratory structure is the liposome, a spherical lipid bilayer that forms from phospholipids.A structure similar to one or more of these aggregates may have been the precursor of true cells.當(dāng)一個(gè)系統(tǒng)獲得能量時(shí)，可能發(fā)生3種有機(jī)分子的聚集。從多聚物的溶液中俄國(guó)科學(xué)家獲得了富含小液滴的多聚物，即凝聚物。從氨基酸和水的混合液中Fox獲得了類蛋白微球體。實(shí)驗(yàn)室第三個(gè)結(jié)構(gòu)物質(zhì)是脂質(zhì)體，即由磷脂形成的球形脂雙層結(jié)構(gòu)。

Further steps in the appearance of cells on the earth included the development of RNA and DNA as biological information molecules.Evidence suggests that RNA, which can form spontaneously under conditions mimicking those of the early earth, was the first informational molecule.The discovery of RNA ribozymes-RNA that can act as an enzymelike catalyst suggests that such catalytic RNA also could have assembled new RNAs from early nucleotides.Certain catalytic RNAs can also carry out sexlike exchanges of pieces of RNA.RNA可能是地球早期形成的第一個(gè)貯藏信息的物質(zhì)。在實(shí)驗(yàn)室模擬早期地球自然條件下其可自發(fā)形成。核酶的發(fā)現(xiàn)說(shuō)明它可以催化早期核苷酸形成新的RNA。某些催化RNA具備類似于RNA 片段性交換的功能。Following the development of a lipid-protein surface layer and replicating RNA and DNA informational molecules, the events leading to the emergence of living cells would have included the origin of the genetic code;the sequestering of RNA or DNA into cell-like structures;and the development of metabolic pathways.接下來(lái)脂蛋白表層的形成，RNA的復(fù)制,DNA信息分子的形成，最終導(dǎo)致活細(xì)胞的出現(xiàn)，包括最初的遺傳密碼，RNA或DNA被包裹進(jìn)細(xì)胞樣的結(jié)構(gòu)中；及代謝途徑的建立。The Earliest Cells The oldest fossils that may represent living cells are found in rocks that are about 3.5 billion years old.The cells were probably anaerobic heterotrophs, with autotrophs arising much later.The first autotrophs produced their own nutrients and released O,-a metabolic by-product that had a crucial impact on later life forms.The resulting ozone layer in the earth's atmosphere reduced the penetration of ultraviolet light.As a result, cells would survive in shallow water and on the land surface.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.Although the earliest cells were all prokaryotes, by about 1.5 billion years ago eukaryotes appeared.能說(shuō)明活細(xì)胞存在的最古老化石大約有35億年了。最早出現(xiàn)的細(xì)胞可能是厭氧異氧生物，自養(yǎng)生物很久后出現(xiàn)。最早的自養(yǎng)生物自己生產(chǎn)營(yíng)養(yǎng)并釋放氧氣，這個(gè)新陳代謝副產(chǎn)品對(duì)后期生命的形成有一個(gè)深遠(yuǎn)的影響。臭氧層的出現(xiàn)減少了紫外線的滲透。結(jié)果，細(xì)胞就能夠在淺水區(qū)和陸地上生存了。大氣中氧氣數(shù)量的增加使得需氧細(xì)胞進(jìn)化并產(chǎn)生細(xì)胞呼吸，這預(yù)示著全球碳循環(huán)的開(kāi)始。最早期的細(xì)胞都是原核生物，直到15億年后，真核細(xì)胞才出現(xiàn)。The Changing Face of planet Earth Changes in land masses, the seas, and climate have greatly affected the evolution of life on the earth.The basic parts of the planet include a light, solid crust over a hot, semisolid mantle and an inner, partially molten core.Massive segments or plates of the crust move over the mantle in the process of continental drift.Over the past 500 million years, continental drift has sculpted the earth's crusts to produce the form and distribution of present-day continents.Climatic changes that greatly affected living organisms accompanied these plate movements;the period was marked by occasional waves of mass extinctions of living creatures.Organisms were also affected by periods of glaciation that followed variations in the earth's orbit and in the output of energy by the sun.大陸板快，海洋的改變，以及氣候?qū)Φ厍蛏倪M(jìn)化都有深遠(yuǎn)影響。地幔上大板快地殼的擠壓形成大陸漂移。大陸漂移雕塑了地殼的外觀，使現(xiàn)在大陸形成。伴隨板塊運(yùn)動(dòng)，氣候改變對(duì)活有機(jī)體有深遠(yuǎn)影響。在特定時(shí)期的生物大量滅亡高峰是這個(gè)時(shí)期的見(jiàn)證。生物也受冰河期影響，在冰河期，地球軌道和太陽(yáng)能的輸出都發(fā)生了很大變化。

Taxonomy: Categorizing the Variety of living Things Biologists use the binomial system of nomenclature developed by Linnaeus to categorize the varieties of life on the earth.The system assigns each type of organism to a genus and species.Organisms are then further classified into higher taxonomic categories-family, order, class, division(plants), phylum(animals), and kingdom.Evidence from many subfields of biology, such as biochemistry and comparative anatomy, helps define species and higher taxa(taxon).And whereas species were originally defined in terms of morphological traits, today biologists generally use the criterion of a reproductively isolated population.生物學(xué)家利用林奈發(fā)展的雙名法對(duì)生物分類。系統(tǒng)選定每個(gè)類型的生物進(jìn)入屬和種，然后將生物進(jìn)一步分類更高級(jí)類別中，即科，目，綱，門(mén)，界。來(lái)自于生物化學(xué)和比較解剖學(xué)等亞生物學(xué)領(lǐng)域的證據(jù)有助于劃分物種和更高級(jí)的分類單位，然而物種最初依據(jù)形態(tài)學(xué)特征進(jìn)行分類的，今天生物學(xué)家大體上使用生殖隔離群體作為標(biāo)準(zhǔn)。

Taxonomy reveals a great deal about the evolutionary relationships among organisms.A clade is a taxonomic unit whose members are derived from a common ancestor.分類學(xué)揭示了物種間進(jìn)化的大量關(guān)系。進(jìn)化枝中的成員來(lái)自一個(gè)共同的祖先。The Five Kingdoms A phylogenetic tree is a graphic representation of evolutionary relationships.Your text uses a common five-kingdom arrangement: organisms are grouped into the kingdoms Monera, Protista, Fungi, Plantae, and Animalia.Although this system is a convenient organizational tool, the kingdoms are probably no true clades.進(jìn)化系統(tǒng)樹(shù)是進(jìn)化關(guān)系的圖解表現(xiàn)。教材中使用一個(gè)通用的5界：原核生物，原生生物，真菌，植物，動(dòng)物。盡管這個(gè)系統(tǒng)是一個(gè)便利的組織工具，5界劃分可能不是正確的進(jìn)化枝。課后作業(yè)：第一篇閱讀材料 答案：1B,2A,3B,4C,5A,6C

Glossary

Big Bang 大爆炸

An 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.crust 地殼

The crust of the Earth is the outer shell of the Earth, defined by its composition and the properties of some seismic waves.mantle 地幔

The part of the interior of the Earth between the crust and the core.core 核心

The core of the Earth is that part lying below the mantle.coacervate團(tuán)聚體，凝聚層

A collection of organic macromolecules surrounded by water molecules that are aligned to fon-n a sphere.liposome 脂質(zhì)體

A vesicle formed by the homogenization(emulsification)of phospholipids in dilute salt solutions.Liposomes are the prototypes of membrane-bound biologic structures.ozone layer 臭氧層

A layer of the atmosphere, about 20 to 50 km above the surface, which contains ozone produced by ultraviolet radiation.proteinoid類蛋白[質(zhì)] A proteinlike structure of branched amino acid chains that is the basic structure of a microsphere.continental drift 大陸漂移

The theory that the present continents result from the break-up of a larger continent and have moved independently to their present positions.binomial system of nomenclature雙名法

Uses two Latin names, genus and species, for each type of organism.genus 屬(plural, genera)A unit used in the classification of plants and animals.A genus consists of a number of closely related species, and members of the same genus often have a number of obvious characteristics in common by which they can clearly be seen to be related.species 物種

A unit used in the classification of plants and animals.Ideally a species is defined as a group of organisms that interbreed with each other to produce fertile offspring.family 科

A 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 one genus.Family names end in-aceae or-ae in botany and in-ideae in zoology.order 目

A unit used in the classification of plants and animals.An order consists of a number of similar or closely related families or only on family.Names of orders end typically in-ales in plants and in-a in animals.class 綱

A 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.division 門(mén)

A unite used in the classification of plants.A division consists of a number of classes, or occasionally of only on class, with certain important characteristics in common.phylum 門(mén)(復(fù)數(shù) phyla)A unit used in the classification of animals.A phylum consists 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.kingdom 界

In biology, a major category into which living material is classified.taxon 分類單位，分類群(復(fù)數(shù) taxa)A unit of classification of any rank in the hierarchical scale.taxonomy 分類學(xué)

The study of the theory, procedure, and rules of classification of organisms according to the Similarities and differences between them clade 進(jìn)化枝，分化單位

In a cladistic classification, organisms are placed into taxonomic groups called clades when they share characteristics that are thought to indicate common ancestry.Lesson Seven(2學(xué)時(shí))

Fungi: The Great Decomposers

教學(xué)目的：使學(xué)生了解真菌的分類，典型真菌的結(jié)構(gòu)特點(diǎn)，使學(xué)生掌握相關(guān)專業(yè)詞匯以及主要用法。教學(xué)重點(diǎn)：真菌分類的組成及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：5月17日 教學(xué)內(nèi)容：

Characteristics of Fungi

The approximately 175,000 species of fungi include some of the simplest multicellular organisms.Fungi have a variety of lifestyles.They may be saprobes that decompose dead organic matter;they may be parasites which obtain nutrients from living hosts;or they may live in symbiotic relationships with algae or with the roots of higher plants.In spite of these variations, however, all fungi carry out extracellular digestion: they secrete enzymes that digest organic matter, and then they absorb the resulting nutrients.包括最簡(jiǎn)單的多細(xì)胞生物在內(nèi)，真菌大概有175，000種。真菌有多種生命形式。他們可能是分解無(wú)生命的腐生菌；也可能是寄生菌；或者與藻類共生，或者與高等植物共生。不管如何變化，所有真菌都是細(xì)胞外消化。他們分泌酶消化有機(jī)物，然后吸收有效的營(yíng)養(yǎng)物質(zhì)。

Most fungi have the same basic body structure consisting of a main body or thallus composed of filaments called hyphae.In most species the walls of hyphal cells contain chitin.Hyphae in certain species may become specialized to form rhizoids, which serve as rootlike anchors, or they may become the feeding structures known as haustoria.Finally, hyphae may or may not be septate-having cross walls that segregate independent cells, each with at least one nucleus.Lower fungi are coenocytic;that is, they are one mass of cytoplasm that contains multiple nuclei.大多數(shù)真菌有同樣的基本結(jié)構(gòu)，即由菌絲組成的菌體。大多數(shù)真菌的細(xì)胞壁含有明角質(zhì)。某些種類的菌絲可能特化形成假根，具有根樣的固定作用，或者他們成為飼喂結(jié)構(gòu)稱吸器。菌絲或有細(xì)胞隔膜或沒(méi)有細(xì)胞隔膜，但至少有一個(gè)細(xì)胞核。低級(jí)真菌是多核體的，即，一大團(tuán)細(xì)胞質(zhì)含有多個(gè)細(xì)胞核。

Hyphae grow and branch to form a filamentous network called a mycelium.Food is digested and absorbed at the tip of each hyphae;more hyphae are generated as this process continues.As a result, fungi may grow very rapidly.Growth depends on mitosis and the rapid manufacture of cytoplasm;fungal mitosis is unique in that it occurs within the nucleus.Hyphae from genetically distinct individuals may fuse to form a heterokaryon-a single cytoplasm with dissimilar nuclei.菌絲生長(zhǎng)形成分支，進(jìn)而形成網(wǎng)狀結(jié)構(gòu)稱為菌絲體。在菌絲尖端，食物被消化并吸收；這個(gè)過(guò)程能持續(xù)產(chǎn)生更多菌絲。結(jié)果，真菌生長(zhǎng)很快。生長(zhǎng)靠有絲分裂和細(xì)胞質(zhì)的快速產(chǎn)生。真菌的有絲分裂很獨(dú)特，即它只發(fā)生在細(xì)胞核里。遺傳學(xué)明顯不同的菌絲個(gè)體融合形成異核體——同一個(gè)細(xì)胞質(zhì)中含有不同的細(xì)胞核。As nonmotile heterotrophs, fungi must eventually be able to find new sources of nutrients.This function is fulfilled by spores, the fungal reproductive bodies.Spores may be home on aerial hyphae, which discharge spores into the air, and depending on the species they may haploid or diploid.There are two main categories of spores:(1)dispersal spores, which are usually short-lived and are produced in large numbers during active fungal growth;and(2)survival spores, which are usually produced in smaller numbers and at a time in the life cycle when the fungus is under some kind of environmental stress.作為不會(huì)移動(dòng)的異養(yǎng)生物，真菌最終能夠發(fā)現(xiàn)營(yíng)養(yǎng)新資源的。這個(gè)過(guò)程由孢子來(lái)完成，即真菌的生殖體。孢子可能是在氣生菌絲的中心，將孢子釋放到空氣中，依賴物種不同，可能是單倍體也可能是二倍體。有兩種主要的孢子：（1）分散的孢子，通常生命期短，數(shù)量大，主要存在于活躍的菌絲生長(zhǎng)階段；（2）存活孢子，通常產(chǎn)生很少的數(shù)量，在生存壓力條件下的一種生命循環(huán)。Classification of fungi As with some of the other groups you have studied, it is difficult to group fungi according to actual evolutionary relationships.In general, they are classified according to morphology, methods of reproduction, and modes of spore production.On the basis of these features, the single division of the kingdom Fungi, Mycota, is divided into six principal classes.對(duì)真菌依據(jù)實(shí)際進(jìn)化關(guān)系進(jìn)行分類是很困難的?？傮w來(lái)說(shuō)，它們是依據(jù)形態(tài)學(xué)，生殖方式，孢子產(chǎn)生的模式來(lái)分類?；谶@些特性真菌界的門(mén)被分成6個(gè)基本綱。

The lower fungi comprise the groups Chytridiomycetes, Oomycetes, and Zygomycetes.All lack septate hyphae and are commonly coenocytic;spores are formed by asexual means.Of the six fungal classes, only the oomycetes usually have a diploid vegetative state.Oomycetes and chytrids(sometimes called water molds)produce motile, flagellated spores in sporangia.They also produce gametes in gametangia;oomycetes are distinguished by their large, immobile egg cells.In fact, both these groups have such distinctive features that some biologists prefer to classify them as protists rather than fungi.Zygomycetes resemble the other two classes in this group but have nonmotile spores.They are also completely terrestrial, and some form mycorrhizal associations with plant roots.低級(jí)真菌包含壺菌，卵菌綱和接合菌。所有缺乏隔膜的菌絲是通用的多核細(xì)胞的；孢子通過(guò)非性方式產(chǎn)生。只有卵菌綱通常有二倍體的營(yíng)養(yǎng)狀態(tài)。卵菌綱和壺菌在孢子囊中產(chǎn)生能動(dòng)的帶鞭毛的孢子。在配子囊中產(chǎn)生配子；卵菌綱具有非尋常大的靜止的卵細(xì)胞。實(shí)際上，這兩大群具有不同的特征，生物學(xué)家寧愿把它們歸為原生動(dòng)物而不是真菌。接合菌與其它兩綱相似，但它的孢子不會(huì)動(dòng)。它們完全是陸生的，一些菌根與某些植物的根形成共生關(guān)系。

The higher fungi include the class Ascomycetes, the largest class of fungi.Most ascomycetes are either saprobes or parasites.Asexual reproduction produces spores called conidia, which develop on the tips of specialized aerial hyphae.In the ascomycete sexual cycle, hyphae of different mating strains fuse, giving rise to ascospores that form in a small, saclike ascus.Groups of asci form fruiting bodies.Ascomycetes of interest to humans include truffles, yeasts, and Penicillium species.高級(jí)真菌包括子囊菌綱，最大的真菌綱。大多數(shù)子囊菌要么是腐生菌，要么是寄生菌。非性繁殖產(chǎn)生的孢子稱分生孢子子實(shí)體，其依賴特化的氣生菌絲尖。在子囊菌性循環(huán)過(guò)程中，不同的菌絲通過(guò)株融合進(jìn)行匹配，產(chǎn)生的子囊菌存在于小類子囊中。子囊群形成果實(shí)體。對(duì)人類有利的子囊菌包括塊菌，酵母和產(chǎn)青霉素菌。

Most members of the class Basidiomycetes—the second group of higher fungi form visible fruiting bodies.A prime characteristic distinguishing basidiomycetes from ascomycetes is the dense mass of dikaryotic hyphae called the basidiocarp-the “mushroom” seen on damp lawns and the forest floor.Club-shaped basidia, each bearing four haploid basidiospores, line the surfaces of the gills on the underside of the mushroom cap.Members of this group undergo both sexual and asexual reproductive processes at different times in their life cycle, and in response to varying environmental influences.綱中大多數(shù)菌為擔(dān)子菌，第二大類高級(jí)真菌，能形成可見(jiàn)的果實(shí)體。擔(dān)子菌與子囊菌相比，最基本不同是它具備濃密的雙核菌絲，稱擔(dān)子果。棒形擔(dān)子，每個(gè)都含有4個(gè)單倍體的擔(dān)子孢子，線形地排列在蘑菇帽下的菌褶表面。大多數(shù)成員有性和非性繁殖兩種，在不同生命循環(huán)中有不同形式，并依據(jù)環(huán)境變化而變化。The class Deuteromycetes, or Fungi Imperfecti, includes a variety of fungi that lack modes of sexual reproduction.Most are known to reproduce asexually by means of conidia.Deuteromycetes important to humans include those used to ferment soybeans and rice to make soy sauce and sake respectively, and those responsible for producing citric acid and the highly dangerous aflatoxin.半知菌綱，包括大量無(wú)性繁殖的真菌。分生孢子完成非性繁殖。對(duì)人類很重要的半知菌綱包括發(fā)酵大豆成醬油和大米發(fā)酵成清酒的菌類，它們也產(chǎn)生檸檬酸和有毒的黃曲霉毒素。Lichens: The Ultimate Symbionts Lichens are composite organisms in which about 90 percent of the lichen mass consists of one species of fungus, while the remaining 10 percent is made up of one or two species of algae.The algal portion of the lichen provides the fungal portion with essential nutrients, while the presence of the fungal component may enable the alga to exploit an otherwise unavailable ecological niche.Lichen fungi are usually ascomycetes, although the other two higher fungi are sometimes found in lichens.Lichens have a number of remarkable features, including their ability to become almost completely desiccated without drying and their ability to absorb inorganic nutrients.Reproduction in lichens is not well understood.地衣是復(fù)合生物，大概90%的地衣團(tuán)由一種地衣組成，10%含有一兩種藻類。藻類為真菌提供必要的營(yíng)養(yǎng)，真菌為藻類提供了難得的小生態(tài)環(huán)境。地衣真菌通常是子囊菌，有時(shí)在地衣中也能發(fā)現(xiàn)其他兩類真菌。地衣有大量的顯著特征，包括在幾乎脫水條件下仍能吸收無(wú)機(jī)養(yǎng)分。地衣繁殖方式還不清楚。Fungal Evolution The various fungi may have arisen independently from prokaryotes, since some evidence suggests that ascomycetes and basidiomycete did not evolve from known lower forms.However, all fungi do show the same dependence on nutrients produced by plants, animals, or algae.各種真菌可能都獨(dú)立進(jìn)化于原核生物，有證據(jù)表明，子囊菌和擔(dān)子菌沒(méi)有進(jìn)化。但所有真菌都依賴由植物，動(dòng)物或藻類產(chǎn)生的營(yíng)養(yǎng)。課后作業(yè)：閱讀材料一 答案：1B,2B,3A

Glossary

saprobe 腐生菌

An organism that lacks the ability of photosynthesis, and lives on dead or decaying organic matter, a saprophyte.hyphae 菌絲(復(fù)數(shù)hypha)

Fungal filaments that develop from the growth of germinating spores.They are the fundamental elements of a mycelium.rhizoid 假根

One of many uni-and multicellular filamentous outgrowths that are produced by some algae and by the gametophytes of bryophytes and pteridophytes and function as roots.haustorium吸器（復(fù)數(shù)haustoria)A specialized structure of some parastic plants(e.g., dodder, mistletoe etc.)which penetrates into the vascular bundles of the host plant to obtain nourishment.mycelium 菌絲體(復(fù)數(shù)mycelia)The tangled mass of hyphae that forms the vegetative body(sometimes terined a thallus)of a fungus.heterokaryon異核體

In somatic cell genetics, the state when two cells have ftised but their nuclei have not yet fused septate有隔膜的，分隔的

Divided by a septum.sporangium 孢子果，孢子囊（復(fù)數(shù) sporangia）A cell within which spores or sporelike bodies are home.Generally, it is an asexual structure of certain fungi gametangium配子囊(復(fù)數(shù)gametangia)A gamete-producing structure or sex organ in plants, i.e.an antheridium, oogonium, or archegonium..ascomycetes子囊菌

A female reproductive structure of some ascomycetes in which plasmogamy occurs prior to ascus formation.conidium分生孢子子實(shí)體(復(fù)數(shù)conidia)An asexual spore of certain fungi that is abstracted from the tip or the side of special hyphae called conidiophores.Conidia may consist of one cell or of several cells;in the latter case the septa may be longitudinal, transverse, or mixed.ascus子囊(復(fù)數(shù)asci))The characteristic structure producing sexual spores in the Ascomycetes.basidiomycetes擔(dān)子菌綱

A group of mycelial fungi(Eumycophyta)whose sexual reproduction results in the formation of basidia, which(except in the rusts and smuts)are home on basidiocarps.basidiocarp擔(dān)子果

A fruiting body of the higher basidiomycete fungi.Basidiocarps are the most obvious manifestations of these fungi and include mushrooms, toadstools, and similar bodies.basidium擔(dān)子(復(fù)數(shù)basidia)

The characteristic structure producing sexual spores in the Basidiomycetes.Fungi Imperfecti(Deuteromycetes)半知菌屬，半知菌亞門(mén)

A group of fungi with septate mycelia in which sexual reproduction is either lacking or is not known.Many of these fungi are of great importance as they cause diseases in plants, animals, and man.lichen 地衣

Thallophyte plants composed of a fungus and an alga in such close symbiosis that they form a vegetative plant body that is morphologically different from either of the constituents.Lesson Eight

Animal Development

教學(xué)目的：使學(xué)生了解動(dòng)物的生育過(guò)程，胚胎發(fā)育的結(jié)構(gòu)特點(diǎn)，使學(xué)生掌握相關(guān)專業(yè)詞匯以及主要用法。教學(xué)重點(diǎn)：動(dòng)物發(fā)育過(guò)程及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：5月24日 教學(xué)內(nèi)容：

Production of Sperm and Eggs

In sexually reproducing organisms males and females produce sex cells, known as gametes.These are swimming sperm in males and ova(eggs)in females.在性繁殖過(guò)程中，生物的雄性和雌性產(chǎn)生性細(xì)胞，稱配子。雄性是能夠游動(dòng)的精子，雌性是卵子。The process of sperm production, spermatogenesis, takes place in testes.The sperm originate in gonial cells(spermatogonia)in the walls of seminiferous tubules.Spermatocytes produced by mitosis in spermatogonia divide meiotically to generate haploid spermatids.The mature sperm has a tail, a nucleus containing haploid chromosomes, and a front end with an acrosome, the storage site for enzymes that will aid fertilization.精子產(chǎn)生過(guò)程，即精子發(fā)生在睪丸中。精子產(chǎn)生于輸精管壁的性母細(xì)胞（精原細(xì)胞）。精原細(xì)胞經(jīng)有絲分裂再減數(shù)分裂產(chǎn)生單倍體精子細(xì)胞，即精母細(xì)胞。成熟精子有尾部，單倍體染色體組，頭部有頂體，內(nèi)部?jī)?chǔ)存酶類，有助于受精。

Ova, which are produced during oogenesis, are generated in gonial cells(oogonia)of the female's ovaries.Oocytes then enter a stage of arrest in early meiosis.At a species-specific later point, a final ripening(ovulation)and the first meiotic division occur.A second meiotic division, followed by development of the embryo, takes place if the egg is fertilized.在卵子發(fā)生過(guò)程中，由卵巢中的性母細(xì)胞產(chǎn)生。卵母細(xì)胞進(jìn)入減數(shù)分裂的抑制階段。第一次減數(shù)分裂產(chǎn)生一個(gè)成熟卵。如果卵受精，那么第二次減數(shù)分裂伴隨胚胎的發(fā)育。

Eggs vary greatly in size from species to species and have complex structures.Virtually all developing animal ova are surrounded by helper cells, either follicle cells or nurse cells.Depending on the species, eggs also store varying amounts of yolk, a reservoir of nutrients produced by digestive-gland cells in the mother's body.Finally, follicle cells or cells of the maternal oviduct provide protective coatings for the egg, including albumen(egg white)and various types of outer membranes and shells.品種間卵的大小變化很大，并且有復(fù)雜的結(jié)構(gòu)。實(shí)際上，所有發(fā)育過(guò)程中的卵都輔助細(xì)胞環(huán)繞，要么是濾泡細(xì)胞，要么是撫育細(xì)胞。依賴物種的不同而不同，卵黃貯備也不同，即由母體消化腺細(xì)胞產(chǎn)生的營(yíng)養(yǎng)儲(chǔ)備。最后，濾泡或母體輸卵管細(xì)胞產(chǎn)生保護(hù)性的卵膜，包括清蛋白和各種外部膜及殼。

Frog oocytes have served as model systems for studies of oocyte development.During maturation they produce huge numbers of ribosomes through gene amplification.Large quantities of mRNA may also be made and stored.蛙卵母細(xì)胞作為卵母細(xì)胞發(fā)育的研究系統(tǒng)模型。在成熟過(guò)程中，通過(guò)基因擴(kuò)增產(chǎn)生大量的核糖體。同時(shí)也產(chǎn)生和儲(chǔ)備了大量的mRNA。Fertilization: Initiating Development Fertilization unites male and female gametes and initiates development.In some species fertilization is external;in others(including most terrestrial animals)it takes place internally.The first contact of the sperm head with the egg's jelly coat triggers the acrosome reaction, in which enzymes are released to digest a hole through the egg's protective layers, and the plasma membrane of the sperm is brought into position to bind to the ovum's surface.After fusion of the egg and sperm plasma membranes, the haploid male nucleus with its chromosomes moves into the egg cytoplasm.Fusion also triggers the egg's final meiotic reduction divisions.When sperm and egg nuclei unite, the two sets of chromosomes mingle to create a diploid set.The fertilized egg is now a zygote.雌雄配子結(jié)合作用稱受精作用，發(fā)育開(kāi)始。某些物種中，是外部受孕；另一些物種，包括大部分陸生動(dòng)物，是內(nèi)部受孕。當(dāng)精子和卵子的膠狀膜發(fā)生接觸時(shí)，觸發(fā)了頂體反應(yīng)。釋放多種酶而將卵保護(hù)膜消化出一個(gè)洞。精子的原生質(zhì)膜與卵子的表面連接起來(lái)。精卵原生質(zhì)膜融合后，單倍體雄性核進(jìn)入卵細(xì)胞質(zhì)。融合也觸發(fā)了最后的減數(shù)分裂。當(dāng)精卵核結(jié)合時(shí)，兩套染色體混合產(chǎn)生一二倍體，即受精卵。

The egg's cortical reaction serves as a barrier to the entry of more than one sperm.Initially, there is a temporary change in the egg's electrical state, and the egg cell is activated.The final stage of the reaction, the rapid elevation of the fertilization membrane, prevents further sperm penetration.卵皮層阻止其他的精子進(jìn)入，充當(dāng)壁壘作用。開(kāi)始時(shí)，卵電位發(fā)生暫時(shí)變化，卵細(xì)胞被激活。反應(yīng)最后階段，受精卵的膜快速隆起，阻止更多精子進(jìn)入。

In some species fertilization is not necessary.Instead, parthenogenesis takes place: the egg is spontaneously activated and proceeds to normal embryonic development.對(duì)某些物種而言，受精不是必須的。孤雌生殖，即卵自發(fā)地被激活并進(jìn)入正常的胚胎發(fā)育過(guò)程中。Cleavage: An Increase in Cell Number Cleavage, the major developmental event immediately following fertilization, is a special form of cell division(mitosis).Cleavage produces a blastula, a sheet of cells rounded into a sphere that in most species surrounds a cavity.In the process, the single-celled zygote is divided into many small cells, and yolk, mRNA, ribosomes, and other materials arc distributed to each cell in precise ways.The cells of the blastula, called blastomeres, also each receive a full diploid set of chromosomes.受精后，立即發(fā)生卵裂，細(xì)胞有絲分裂的特殊過(guò)程。卵裂產(chǎn)生一個(gè)囊胚，形成的細(xì)胞壁球形排列形成一個(gè)空腔。在這個(gè)過(guò)程中，單細(xì)胞的受精卵分裂成許多小細(xì)胞，卵黃，mRNA，核糖體和其他物質(zhì)被精確分配到每個(gè)細(xì)胞中。這些囊胚細(xì)胞，稱卵裂球，每個(gè)細(xì)胞都有一套二倍體染色體組。

There are different patterns of cleavage in different species.The amount of yolk present in the egg is a major factor in determining the pattern: in species having little yolk(such as mammals)the zygote cleaves completely through, forming cells that are roughly equivalent in size.In frogs, in which the egg has somewhat more yolk, cleavage proceeds more rapidly in regions of the embryo having less yolk.In bird eggs the yolk is so massive that cleavage divisions are restricted to a tiny area of cytoplasm.不同物種，卵裂方式不同。決定因素主要取決于卵黃的含量。含有少量卵黃的物種（例如哺乳動(dòng)物），合子分裂得很徹底，子細(xì)胞大致平均分裂。蛙卵，卵黃稍微多點(diǎn)，在胚胎的卵黃較少區(qū)域發(fā)育更快些。鳥(niǎo)卵卵黃很大，卵裂被限制在細(xì)胞質(zhì)很小區(qū)域內(nèi)。

In many species the precise distribution to blastomeres of molecular determinants in the cytoplasm is crucial to proper development of different cell types in the embryo.In mammal and bird species the fate of cells is determined by the position of a cell late in cleavage.細(xì)胞質(zhì)中分子遺傳因素精確分配到卵裂球中，對(duì)許多物種而言，是發(fā)育成胚中不同類型細(xì)胞關(guān)鍵所在。對(duì)哺乳動(dòng)物和鳥(niǎo)類而言，細(xì)胞的命運(yùn)最終由細(xì)胞分裂后所處的位置決定的。Gastrulation: Rearrangement of Cells（原腸胚：細(xì)胞重排列）

The rearrangement of the blastula into a three-dimensional organism with inner, middle, and outer layers occurs during gastrulation.The resulting gastrula consists of an outer ectoderm, an inner endoderm, and a mesoderm layer positioned between them.在原腸胚形成過(guò)程中，囊胚重新排列，形成包括內(nèi)層，中層，外層的三圍組織。最終原腸胚由一個(gè)外腸胚，內(nèi)腸胚，和一個(gè)中腸胚構(gòu)成。

Each layer gives rise to specific tissues during embryonic development.A variation in gastrulation, involving the movement of cells into endodermal and mesodermal positions through the thickened primitive streak, arose in reptiles and can still be seen in bird and mammalian embryos, lending support to the theory that birds and mammals evolved from reptiles.每個(gè)胚層產(chǎn)生特殊的胚胎組織。密實(shí)的原腸胚通過(guò)細(xì)胞運(yùn)動(dòng)進(jìn)入內(nèi)胚層和中胚層，爬蟲(chóng)，鳥(niǎo)，哺乳動(dòng)物的胚胎都如此。因此提出這樣的理論，鳥(niǎo)類和哺乳動(dòng)物是由爬蟲(chóng)進(jìn)化而來(lái)的。Organogenesis: Formation of Functional Tissues and Organs The organs and tissues of the embryo arise during organogenesis as cells inside the embryo and on its surface become specialized.Organogenesis actually includes two closely linked processes, morphogenesis and differentiation.During morphogenesis cells and cell populations change shape: an example is neurulation in vertebrate embryos, in which the edges of the flat neural plate fold upward and fuse, forming the beginnings of the hollow brain and spinal cord.During differentiation cells mature so that they may perform separate functions.This maturation may include taking on a function-related shape, such as the long, spindly shape of skeletal-muscle cells.Cell differentiation also results in responsiveness-the ability of a cell to be regulated within the organism through the action of hormones, neurons, and other signals.胚經(jīng)過(guò)內(nèi)部細(xì)胞和表面細(xì)胞特化后，器官形成，發(fā)育成器官和組織。器官形成實(shí)質(zhì)上包括兩個(gè)聯(lián)系緊密的過(guò)程，即形態(tài)發(fā)生和分化。在形態(tài)發(fā)生期間，細(xì)胞和細(xì)胞群體形狀發(fā)生改變：例如，脊椎動(dòng)物的神經(jīng)胚，扁平神經(jīng)板的邊緣向上折疊并融合，是中空大腦和脊髓神經(jīng)形成的開(kāi)端。在分化期間，細(xì)胞成熟，執(zhí)行各自功能。成熟包括功能相關(guān)的成型過(guò)程。例如，細(xì)長(zhǎng)的骨骼肌肉細(xì)胞。細(xì)胞分化也產(chǎn)生應(yīng)答能力，即細(xì)胞受生物體內(nèi)激素，神經(jīng)和其他信號(hào)的調(diào)控過(guò)程。Embryonic Coverings and Membranes The embryos of land vertebrates are enclosed within four extraembryonic membranes that afford protection while still permitting the exchange of gases, nutrients, and other materials.脊椎動(dòng)物的胚胎被4層膜包被，起保護(hù)作用，但仍能交換氣體，營(yíng)養(yǎng)和其他物質(zhì)。Growth: Increase in Size Growth in embryos is largely due to an increase in the number of cells rather than to an increase in the size of individual cells.In many species the extent of embryonic growth is limited by the availability of food(yolk).In animals that develop entirely free of the maternal body, such as frogs and insects, the embryo give rise to a larval stage that can feed itself and later undergo metamorphosis to attain the adult stage.In many species the most spectacular growth phase takes place during the juvenile and adolescent phases of the life cycle.Actual growth generally stops once the organism reaches its typical adolescent phases of the life cycle.Actual growth generally stops once the organism reaches its typical adult size, although replacement of dead cells may continue.胚的生長(zhǎng)很大程度取決于細(xì)胞數(shù)量的增加而不是單個(gè)細(xì)胞大小的改變。在大多數(shù)物種中，胚的生長(zhǎng)是受卵黃的量限制的。在動(dòng)物細(xì)胞中，完全依賴于母體，例如蛙和昆蟲(chóng)，胚產(chǎn)生幼蟲(chóng)狀態(tài)，后來(lái)經(jīng)歷變態(tài)而進(jìn)入成年?duì)顟B(tài)。在許多物種中，在少年和青春期，發(fā)生特別顯著的生長(zhǎng)。一旦細(xì)胞進(jìn)入成年?duì)顟B(tài)和成年大小，生長(zhǎng)就停止了，盡管死細(xì)胞的替代不斷發(fā)生。

A special type of growth, regeneration of lost body parts, can take place in adults of some species.Prior to such regeneration cells in stump tissue undergo dedifferentiation.They lose their functional phenotype, divide rapidly, and generate a population of cells that will regenerate the lost part.Compensatory hypertrophy is a different, temporary growth response in which residual tissue increases in mass and cell number: cells undergo mitosis but do not dedifferentiate.一個(gè)特殊類型的生長(zhǎng)，再生失去的部分軀體，發(fā)生在某些物種的成體中。在再生之前，殘肢組織細(xì)胞經(jīng)歷了去分化過(guò)程。他們失去功能表型，快速分裂，產(chǎn)生細(xì)胞群來(lái)再生失去的部分。代償式肥大是一個(gè)不同的，暫時(shí)的生長(zhǎng)應(yīng)答過(guò)程，殘余組織在體積和細(xì)胞數(shù)量上增加：細(xì)胞經(jīng)歷了減數(shù)分裂，但沒(méi)有去分化過(guò)程。Aging and Death: Final Developmental Processes Aging is an ongoing, time-dependent developmental process in which body parts deteriorate.Proposed causes include the degeneration of collagen(the fibrous proteins of the connective tissues)and limits on the number of times cells can divide.Other theories focus on a decline of the immune system or on the accumulation of lipofuscins(aging pigments).老化是一個(gè)持續(xù)過(guò)程，隨時(shí)間發(fā)育，身體部分惡化?？赡茉虬z質(zhì)的退化（纖維蛋白）和能分裂活細(xì)胞的限制。另外理論認(rèn)為，免疫系統(tǒng)的免疫下降或脂褐素的堆積造成的。課后習(xí)題：閱讀材料一

Glossary

sperm精細(xì)胞

Cells that develop from the spermatids by losing much of their cytoplasm and developing long tails;the male gamete.ovum 卵，卵子（復(fù)數(shù),ova）

An unfertilized non-motile female gamete.In many animals it is produced in the ovary.spermatogenesis 精子發(fā)生

The specific name given to the gametogenesis process that leads to the formation of sperm.oogenesis 卵子發(fā)生-The specific name given to the gametogenesis process that leads to the formation of eggs.ovaries 卵巢，子房

The female sex organs the produce haploid sex cells, the eggs or ova.yolk 卵黃，蛋黃

The store of food material, mostly protein and fat, that is present in the eggs of most animals oviduct 輸卵管

The tube(fallopian tube)that carries the primary oocyte to the uterus.gene amplification 基因擴(kuò)增

A temporary dramatic increase in the numbers of a particular gene in a genome during one developmental period.fertilization 受精

The joining of haploid nuclei, usually from an egg and a sperm cell, resulting in a diploid cell called the zygote.Zygote受精卵

A diploid cell that results from the union of an egg and a sperm.acrosome reaction 頂體反應(yīng)

That series of observable, structural changes undergone by a sperm when in the vicinity of an ovum in the oviduct.Specifically, many openings appear in the sperm head membrane, through which the contents of the acrosome appear to be released.parthenogenesis ['pa:einE]u'd3enisis]單性生殖，孤雌生殖

Reproduction in which eggs develop normally without being fertilized by a male gamete, producing an individual usually genetically identical to the parent.cleavage 卵裂

The mitotic division of the zygote that occurs immediately after fertilization and produces a ball of smaller cells without an overall increase in size.blastula 囊胚，囊胚泡

The stage of the early animal embryo that succeeds cleavage and precedes gastrulation.A blastula is usually made up of a hollow ball of cells, with a wall one to several cells thick;the central cavity is the blastocoel.blastomere卵裂球

One of several small cells formed from an animal zygote during cleavage.gastrulation 原腸胚形成

The process in the animal embryo by which a blastula is converted into a gastrula, with the laying down of the germ layers.gastrula 原腸胚

The stage in the development of animal embryos that follows the blastula and results from gastrulation.The cells of a gastrula are differentiated into the germ layers and the central cavity opens to the exterior by the blastopore.ectoderm 外胚層，內(nèi)層

The outermost of the germ layers of metazoan embryos.It develops mainly into epidermal tissue, the nervous system, sense organs, and(in lower forms)the nephridia.endoderm 內(nèi)胚層，內(nèi)層

The innermost of the germ layers of metazoan embryos.Mesoderm中胚層，中層

The middle layer of the three germ layers of triploblastic animal embryos.It develops into cartilage, bone, muscle, blood, kidneys, and gonads.primitive streak 原腸胚 A longitudinal band of embryonic mesodermal cells that develops within a dorsal groove along the length of the gastrula of mammals and birds.organogenesis 器官形成 The formation of organs.morphogenesis形態(tài)發(fā)生，形態(tài)建成

The developmental processes leading to the characteristic mature form of an organism or part of an organism.differentiation 分化，鑒別

The complex of changes involved in the progressive diversification of the structure and functioning of the cells of an organism.For a given line of cells, differentiation results in a continual restriction of the types of transcription that each cell can undertake.neurulation神經(jīng)胚形成

Developmental stage in an embryo during which the cells differentiate into the brain and spinal cord.metamorphosis 變態(tài)

The transformation from larval to adult form.regeneration 再生

The replacement by an organism of tissues or organs that have been lost.dedifferentiation 去分化，脫分化

The loss of differentiation, as in the vertebrate limb stump during formation of a blastema.compensatory hypertrophy 代償式肥大 See regeneration.Lesson Nine

The Origin of Species

教學(xué)目的：使學(xué)生了解物種起源相關(guān)理論，使學(xué)生掌握相關(guān)專業(yè)詞匯以及主要用法。教學(xué)重點(diǎn)：物種起源相關(guān)理論及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：5月31日 教學(xué)內(nèi)容：

How Biologists Define a Species Modern biology generally define a species as group of actually or potentially interbreeding populations that is reproductively isolated from the such groups.Members of a species can interbreed with each other, but they cannot breed with organisms belonging to another species.One advantage of the standard of reproductive isolation is that it is very precise.Notice, however, that it can only be applied to organisms that reproduce sexually.Asexual reproducers, including most prokaryotes, many plants, and some animals, must be classified into species on the basis of physical(biochemical or morphological)traits.現(xiàn)代生物學(xué)大體將物種定義為實(shí)際上的一群或潛在的雜交群體，即從這個(gè)群體隔離繁殖的后代。種族中個(gè)體可以互相交配，但種間不能。這種繁殖隔離的一個(gè)優(yōu)勢(shì)是很精確。但僅適用于性繁殖的生物。非性繁殖，包括大多數(shù)原核生物，許多植物，某些動(dòng)物，需要通過(guò)自然特征進(jìn)行歸類。Preventing Gene Exchange Two general types of mechanisms operate to block the exchange of genes between individuals of related groups.The first general type is made up of prezygotic isolating mechanisms that prevent the formation of zygotes.Prezygotic isolation falls into two categories: ecological and behavioral.In the first case, two related group may become adapted to slightly different environments-perhaps varying soil types or food sources.Over time, these genetic differences become so great that successful cross-fertilization can no longer take place.In behavioral isolation, related groups evolve differing behaviors such as specific mating rituals-that restrict the exchange of genes to members of the same group.兩種基因型機(jī)制阻礙了相關(guān)群體中個(gè)體的基因交換。第一種基因型由前合子機(jī)械隔離機(jī)制阻止合子的生成。前合子隔離分兩類：生態(tài)學(xué)的和行為學(xué)的。第一種情況，兩個(gè)相關(guān)群體可能分別適應(yīng)稍微不同的環(huán)境，如土壤類型或食物來(lái)源的變化。長(zhǎng)時(shí)間，這些遺傳差異變得很大而很難異體受精。而行為學(xué)隔離，相關(guān)的群組進(jìn)化成不同的行為方式，例如，結(jié)婚儀式，從而限制了同群成員基因交流。

Sometimes the differences that produce prezygotic isolation involve mechanical isolation.That is, mating is physically impossible between members of different species because genitals of males and females are structurally incompatible or because molecules on the surfaces of sperm and egg fail to bind.A final type of prezygotic mechanism is temporal isolation, in which time-related environmental cues that trigger reproductive processes are different for related species.有時(shí)，產(chǎn)生前合子隔離的差異涉及了隔離機(jī)制。即，由于生殖器結(jié)構(gòu)不匹配或精卵分子表面不結(jié)合而使不同種群成員間不能自然結(jié)合。最后一類前合子機(jī)制是暫時(shí)隔離，與時(shí)間有關(guān)的環(huán)境因素觸發(fā)了相關(guān)物種的不同繁殖過(guò)程。

In postzygotic isolating mechanisms mating occur, but the resulting hybrid organism is inviable or sterile.In a special case of hybrid sterility termed hybrid breakdown, the second and subsequent generations after a cross show reduced reproductive success.Contrast this fact with the very different outcome of crossbreeding between two genetically distant members of the same species, where the result is often heterozygote advantage(hybrid vigor).在合子后隔離機(jī)制中，匹配可以進(jìn)行，但或不產(chǎn)生雜種或雜種不育。雜種不育在某些特殊情況下，是指第二代或以后幾代顯示出雜交繁殖能力的降低。正是同種遠(yuǎn)基因成員間的雜交產(chǎn)生不同的結(jié)果，而產(chǎn)生雜種優(yōu)勢(shì)。

Populations of a species that are spread out over a broad geographical range are often arrayed in a cline-a gradual change in one or more characteristics as each population evolves adaptations to its own local environment.Along a cline, subspecies with distinct characteristics may arise.Often, individuals at either end of a cline are reproductively isolated.地域上分布很廣的種的群體中，經(jīng)常存在變異群，因?yàn)檫m應(yīng)當(dāng)?shù)氐沫h(huán)境，每個(gè)群體逐漸產(chǎn)生一個(gè)或多個(gè)與眾不同的特點(diǎn)。在變異群中，帶有明顯特征的亞群可能產(chǎn)生。通常，在兩個(gè)變異群中的個(gè)體是繁殖隔離的。Becoming a Species: How Gene Pools Become Isolated Ernst Mayr's model of allopatric speciation proposes that species can originate in a two-stage process.In the first stage, populations of existing species are separated by a physical or geographical barrier.As a result, over time genetic differences leading to pre-or postzygotic isolation arise between the two groups.In the second stage, the diverged populations may again come into contact.If this happens, speciation becomes complete through the action of natural selection.異地物種形成模型認(rèn)為，物種可能起源于兩個(gè)階段。第一階段，已經(jīng)存在的物種群體可能由于自然或地理屏障被隔離。結(jié)果，長(zhǎng)時(shí)間后，在兩個(gè)群體間遺傳差異導(dǎo)致前合子或后合子隔離的產(chǎn)生。第二階段，這些趨異群體可能再次接觸，物種發(fā)生可能通過(guò)自然選擇發(fā)生。The Genetic Bases of speciation The extent of differences between populations that are diverging into separate species or between species that have already diverged is represented by a statistic called genetic identity-the relative proportion of the same structural genes present in members of groups being compared.In general, biologists believe that the genetic events leading to speciation take place gradually.Once a new species has arisen, it tends to diverge genetically from related species at a more rapid pace.In some cases, such as the primate order, major differences in body form are not reflected by corresponding divergences in structural genes.This has led Biologists to hypothesize that small changes in regulatory genes may account for many of the large-scale changes responsible for sepciation and the origin of higher taxonomic groups.能夠趨異的群體或已經(jīng)趨異的物種，他們之間差異的擴(kuò)大，由一個(gè)穩(wěn)定的遺傳識(shí)別代表。即在可比群體成員中相同基因所占相關(guān)比例。大體而言，生物學(xué)家相信，遺傳導(dǎo)致的物種形成是逐漸發(fā)生的。在某些情況下，身體主要差別并不能反映結(jié)構(gòu)基因的趨異，生物學(xué)家因此提出，調(diào)控基因很少的改變可能導(dǎo)致很大規(guī)模物種改變和更高分類學(xué)上群體的產(chǎn)生。

One mechanism that may rapidly split populations genetically is polyploidization—the sudden multiplication of an entire complement of chromosomes.This can result in sympatric speciation, in which new species arise even though no geographical isolation has taken place.A phenomenon similar to polyploidization involving the rearrangement of chromosomes has been proposed to explain the evolutionary origin of giant pandas.Clearly, species can originate in a variety of ways.遺傳學(xué)上可以快速分離群體的一個(gè)機(jī)制是多倍體，一個(gè)完全互補(bǔ)染色體組的突然倍增。結(jié)果導(dǎo)致同域物種形成，即使沒(méi)有地理隔離也會(huì)產(chǎn)生新的物種。與多倍體相似的一個(gè)現(xiàn)象是染色體重排，可以解釋巨大熊貓的進(jìn)化起源。顯然，物種可以以多種方式進(jìn)化。Explaining Macroevolution: Higher-order Changes The changes that generate species are sometimes termed microevolution;those that produce the major phenotypic differences that separate genera, classes, orders, and so on are termed macroevolution.Some lines of descent can be traced by studying the fossil record.In other cases relationships must be inferred by comparison of related living organisms.When lines of descent over evolutionary time are constructed, the result is a phylogeny.遺傳物種的改變有時(shí)稱微進(jìn)化；那些產(chǎn)生很大差異用來(lái)區(qū)分屬，綱，目的表型變化稱大幅進(jìn)化。某些品系的后代可以通過(guò)化石追根溯源。而其他相關(guān)性可以通過(guò)現(xiàn)存活體的比較來(lái)推論。當(dāng)品系后代以進(jìn)化鐘構(gòu)建時(shí)，形成系統(tǒng)發(fā)育樹(shù)。

The rationale for building a phylogeny is simple: it assumes that similarities in body structure, biochemistry, reproductive strategies, and other features of organisms can be used to trace lines of common descent.The process is complex because evolution proceeds in different patterns.In cases of parallel evolution, two or more lineages evolve along similar lines.In convergent evolution, very distantly related lineages become more alike as similar adaptations take hold in response to demands of the environment.Thus similar structures in different organisms may reflect homology(derivation from a common ancestor)or analogy(independent origin of structures used for similar purposes).建立系統(tǒng)發(fā)育樹(shù)的基本理論很簡(jiǎn)單：把身體結(jié)構(gòu)，生物化學(xué)，繁殖策略以及其他特征相似的生物劃分進(jìn)同一個(gè)品系。這個(gè)過(guò)程很復(fù)雜，因?yàn)檫M(jìn)化經(jīng)歷不同模式。就平行進(jìn)化而言，兩個(gè)或更多的血統(tǒng)沿相似品系進(jìn)化。在相似生存條件下，親源關(guān)系很遠(yuǎn)的血統(tǒng)也可能更相似。不同生物間的相似結(jié)構(gòu)可能說(shuō)明它們具有同源性。

One of the most common evolutionary patterns that can be constructed from the fossil record is divergent evolution or radiation.It is represented by the branching and rebranching of a single line.Another common feature of evolution is extinction-the complete loss of a species or group of species.Mass extinctions have occurred at least five times in the earth's history.從化石證據(jù)構(gòu)建的最普通進(jìn)化模式是趨異進(jìn)化。由分支和次級(jí)分支的簡(jiǎn)單線條代替。另一個(gè)進(jìn)化的共同特征是滅絕。地球歷史中至少發(fā)生過(guò)5次大規(guī)模的滅絕。

Gaps in the fossil record have led some paleontologists to propose the punctuated equilibrium theory of evolution.The theory holds that evolution proceeds by spurts-radical changes over short(in geological time)periods of time-with intervening periods of equilibrium.The theory is controversial and tends not to be supported when an abundant fossil record is available.化石證據(jù)上的斷代使古生物學(xué)家們提出間斷平衡進(jìn)化理論。這個(gè)理論認(rèn)為進(jìn)化在短期內(nèi)經(jīng)歷了根本突變，中間又介入均衡階段。這個(gè)理論很有爭(zhēng)議，一旦發(fā)現(xiàn)豐富的化石證據(jù)，理論就難支撐了。The Role of microevolution in Macroevolution Biologists have no certain answers to a number of questions about large-scale evolutionary changes.These questions range from whether novel higher taxa result from as-yet undescribed radical genetic processes, to whether known processes such as genetic drift and small gene changes can plausibly account for the evolution of new genera, families, and orders.Investigators are exploring these areas using traditional methods as well as the newer techniques of molecular biology.生物學(xué)家還無(wú)法回答關(guān)于大規(guī)模進(jìn)化的許多問(wèn)題。許多問(wèn)題是新類別的物種可能起源于還不確定的遺傳過(guò)程，或者知道遺傳過(guò)程，例如，遺傳漂移和少量基因的改變可能是新屬，科，目產(chǎn)生的原因?？蒲泄ぷ髡卟坏脗鹘y(tǒng)方法對(duì)這些領(lǐng)域進(jìn)行研究，還利用分子生物學(xué)新科技。Glossary

hybrid sterility 雜種不育性

The failure of hybrids between different species to produce viable offspring.cline 梯度變異，變異群

A smooth gradation of characteristics from one end of the range of a species to the other, usually brought about by gradients of climate, soil, or other environmental variables.allopatric speciation

異域物種形成，異地物種形成

The development of distinct species through differentiation of populations in geographic isolation.sympatric speciation

同域物種形成，同地物種形成

Speciation that follows after ecological, behavioral, or genetic barriers arise within the boundaries of a single population.This can happen instantaneously, as when polyploidy arises in a type of flowering plant that can self-fertilize or reproduce asexually.microevolution 微進(jìn)化，種內(nèi)進(jìn)化

Changes in allele frequencies brought about by mutation, genetic drift, gene flow, and natural selection.macroevolution 宏觀進(jìn)化，大進(jìn)化，種外進(jìn)化

The large-scale patterns, trends, and rates of change among groups of species.phylogeny 種系發(fā)生，系統(tǒng)發(fā)生，系統(tǒng)發(fā)育

Evolutionary relationships among species, starting with most ancestral forms and including the branches leading to their descendants.parallel evolution平行進(jìn)化

The evolution of organisms that were originally very similar and have both evolved in the same direction.(Contrast with convergent evolution)convergent evolution

趨同進(jìn)化

An evolutionary pattern in which widely different organisms show similar characteristics.Homology 同源性，同種性，同系性

A similarity between two structures that is due to inheritance from a common ancestor.The structures are said to be homologous.(Contrast with analogy)analogy 相似，同功

A resemblance in function, and often appearance as well, between two structures which is due to convergence in evolution rather than to common ancestry.(Contrast with homology)divergent evolution 趨異進(jìn)化

A basic evolutionary pattern in which individual speciation events cause many branches in the evolution a group of organisms.extinction 滅絕，熄滅，消失

In genetics, inhibition of the expression of differentiated properties in hybrid cells from differentiated and undifferentiated parental cells.punctuated equilibrium 間斷平衡

Evolutionary theory that holds that morphological changes occur rapidly in time;during speciation these changes occur in small populations with the resulting new species being distinct from the ancestral form.After speciation, species retain much the same form until extinction;distinct from the phyletic gradualism theory.Lesson Ten

The Ecology of Populations

教學(xué)目的：使學(xué)生了解物種群體生態(tài)學(xué)相關(guān)理論，使學(xué)生掌握馬爾薩斯人口理論及相關(guān)專業(yè)詞匯和主要用法。

教學(xué)重點(diǎn)：馬爾薩斯人口理論及相關(guān)英語(yǔ)詞匯的掌握。教學(xué)難點(diǎn)：專業(yè)英語(yǔ)詞匯的記憶

講授方法：以學(xué)生翻譯為主，老師講解相關(guān)專業(yè)知識(shí)輔助學(xué)生理解 授課時(shí)間：5月31日 教學(xué)內(nèi)容：

Population Growth

Populations-groups of individuals belonging to the same species-all have three very significant statistical characteristics: per capita birth rate or natality;per capita death rate or motality;and number of individuals per unit area or density.種群中的每個(gè)個(gè)體都屬于同一個(gè)物種，具有三個(gè)非常顯著的統(tǒng)計(jì)學(xué)特征：出生率；死亡率；種群密度。As first described by Malthus, a population theoretically can grow exponentially(geometrically)if there are no limits on resources such as food or hiding places and no predation(ac of population growth is represented by an exponential growth curve.The condition exponential growth rarely occur in nature, however.The finite levels of resources in any environment set an upper limit to population size—termed carrying capacity(K)—that can be reached but never long exceeded.A logistic growth curve plots the leveling-off of growth when population size reaches equilibrium with available resources.馬爾薩斯首次闡述了人口理論，他指出，如果沒(méi)有類似于食物，庇護(hù)所等資源的限制，沒(méi)有被捕食，群體總量的增長(zhǎng)符合指數(shù)或幾何關(guān)系。即指數(shù)生長(zhǎng)曲線。但，這種指數(shù)生長(zhǎng)在自然界中很少發(fā)生。環(huán)境中有限的資源限制了群體規(guī)模，即環(huán)境的容納量，只能接近而不能超過(guò)。當(dāng)群體規(guī)模接近可獲得資源的最大平衡態(tài)時(shí)，邏輯生長(zhǎng)曲線呈現(xiàn)負(fù)增長(zhǎng)。When resource limits are approached or exceeded, time is required for the birth rate to fall and for the death rate to rise.This response time is known as reproductive time lag.It is one reason for the fluctuations in numbers that are seen in every population.In many natural populations, carrying capacity(and hence population size)fluctuates seasonally.If a population drastically exceeds the carrying capacity of its environment temporarily, damage may occur that permanently lowers environmental carrying capacity.當(dāng)接近或超過(guò)資源限制時(shí)，出生率下降，死亡率升高。這段時(shí)期稱繁殖滯后時(shí)期。這種群體數(shù)量的波動(dòng)存在于每一個(gè)群體中。在自然群體中，群體數(shù)量隨季節(jié)波動(dòng)。若暫時(shí)超出環(huán)境的容納量，可能造成對(duì)環(huán)境持久的傷害而保持很低的容納量。

Besides environmental carrying capacity, a population's age structure and reproductive strategy also affect the rate at which the population grows.Age structure reflects the relative numbers of young, middle-aged, and older individuals in a give population.In a population having many members at or nearing reproductive age, significant growth may occur.Age structure may also be represented by a survivorship curve.除環(huán)境容納量外，群體的年齡結(jié)構(gòu)和繁殖方式也影響群體增長(zhǎng)率。年齡結(jié)構(gòu)反映中青老的比例關(guān)系。若生育年齡的比例大，則顯著增長(zhǎng)。存活曲線也可以反映年齡結(jié)構(gòu)。

The reproducing members of a population follow a complex adaptive reproductive strategy that has evolved over millennia.Reproductive strategies generally fit into one of two categories: those of r-selected species and those of K-selected species.In r selection individuals reach reproductive age quickly and produce many offspring., Each offspring is small and enters the world with relatively few resources.Out of the many produced, only a few will survive until reproductive age.In K selection, a strategy related to environmental carrying capacity and the need to compete for resource, individuals mature slowly and produce few offspring.However, parents invest a great deal of resources in each offspring;and after a long period of growth to large size, each offspring's chances of survival until reproductive age are high.幾千年來(lái)，進(jìn)化形成兩個(gè)繁殖策略，一是繁殖周期快，后代數(shù)量多，每個(gè)后代小并可獲得資源少。僅有少量存活到生育年齡。一是和環(huán)境的容納量及可匹配資源有關(guān)，個(gè)體成熟慢并產(chǎn)生很少的后代。但，父母給后代提供很多資源，需要很長(zhǎng)的生長(zhǎng)期，存活到生育年齡的機(jī)遇很高。Limits on Population Size The size of a population is measured in terms of its density.Whether population density is high or low, the distribution of individuals within the population is usually uneven.Common distribution patterns include clumped, uniform, and random.Negative consequences are often attached to high(or rising)population density.These density-dependent factors include increased predation, parasitism, disease, and intraspecific and interspecific competition.Population size may also be reduced by densityindependent factors, a category that includes natural catastrophes.群體的規(guī)模也可以用密度來(lái)衡量。不論群體密度高與低，群體中個(gè)體的分布是不均一的。通用分布模式包括群體的，均勻的，隨機(jī)的。密度依賴因子包括增加了的捕食，寄生，疾病，種內(nèi)競(jìng)爭(zhēng)和種間競(jìng)爭(zhēng)。群體規(guī)模也可因?yàn)槊芏葻o(wú)關(guān)因子而降低，包括自然災(zāi)難。

The interactions of predators and their prey affect population size in complex ways.Such populations sometimes cycle regularly between growth and decline, in part from the effects of reproductive time lags.In general, predation may slow or stop the growth of a prey population only when many reproducing individuals are eliminated.If only weak, sick, or very young prey are taken, the effect of predation on the density of the population as a whole may be slight.捕食和被捕食的相互復(fù)雜關(guān)系影響著群體的規(guī)模。例如群體規(guī)模規(guī)律的增長(zhǎng)和下降，部分是由于繁殖滯后期的影響。總的來(lái)說(shuō)，當(dāng)被捕食的是能繁殖的個(gè)體時(shí)，可能減慢或停止群體的增長(zhǎng)。反之，影響就很微弱。An area of controversy among ecologists is the question of whether species diversity in a community tends to generate stability of whether stability encourages species diversity.One aspect of this argument is the hypothesis that a complex food web is more stable than a simple one.In nature, however, many stable, highly diverse communities are characterized by the presence of numerous simple food webs.It may be that stable environments beget diversity because they allow rare species to persist.生物學(xué)家一直在爭(zhēng)論，是否是物種差異產(chǎn)生穩(wěn)定性還是穩(wěn)定性促成了物種差異。一種假設(shè)認(rèn)為，復(fù)雜的食物鏈要比簡(jiǎn)單的食物鏈更穩(wěn)定。實(shí)際上，許多穩(wěn)定的，高差異的社會(huì)群體是由眾多簡(jiǎn)單食物鏈支撐的?？赡苁欠€(wěn)定的環(huán)境引起差異，它只允許很少的物種存留。How Populations Are Distributed

Just as competition, predation, and other elements interact to determine the size of a population within a community, population distribution is the result of many interrelated factors.Overall, the distribution of a population in its potential range depends on locations of food and suitable habitat, interspecific competition for resources, and other variables.Among plants, one of the most effective forms of interspecific competition for resources is allelopathy.Among species that share similar or identical habitat niches, resource partitioning is often seen.In character displacement, closely related species have evolved physical differences in body structures used for exploiting a limited resource.Eventually, such solutions to the need for dividing up a scarce resource may lead to speciation.正如競(jìng)爭(zhēng)，捕食，和其他因素相互作用影響著群體大小，群體分布是許多相關(guān)因子相互作用的結(jié)果?？傊?，潛在的群體分布取決于食物的位置和穩(wěn)定的住所，種間對(duì)資源的競(jìng)爭(zhēng)，以及其他可變因素。對(duì)于大多數(shù)植物，種間最有效的資源競(jìng)爭(zhēng)是異種相生相克關(guān)系。許多物種分享相似或相同的生存環(huán)境，而進(jìn)行資源劃分。對(duì)于特征替換，關(guān)系更近的物種已經(jīng)在進(jìn)化過(guò)程產(chǎn)生了很大體證差異。最終，這種對(duì)珍貴資源的劃分方式可能導(dǎo)致物種形成。

Human Population: A Case Study in Exponential Growth

The awesome rate of increase that is now a feature of the human population started about 10,000 years ago during the agricultural revolution.At that time, world human population is estimated to have totaled 133 million people;today it has reached a staggering 5 billion.Viewed on a graph, this increase closely resembles the classical exponential growth curve-a growth pattern that cannot be sustained.自從1萬(wàn)年前農(nóng)業(yè)革命以來(lái)，人類人口以驚人的速度增長(zhǎng)著。當(dāng)時(shí)，世界人口估計(jì)在133百萬(wàn)；今天已經(jīng)達(dá)到50億。幾乎接近典型的指數(shù)增長(zhǎng)曲線，一個(gè)不穩(wěn)定的增長(zhǎng)模式。

While the birth rate in many developed countries has slowed, it remains high in less well developed areas of the world.Demographers predict that, if this rate continues, the human population level will reach 30 billion before the end of the twenty-first century.Yet most biologists believe that the earth's carrying capacity for humans is only 10 billion.Clearly, we humans face a serious problem in managing the earth's precious resources while sustaining such a high population density.盡管許多發(fā)達(dá)國(guó)家的出生率降低，但也有高出生率的。人口統(tǒng)計(jì)學(xué)預(yù)測(cè)，若出生率持續(xù)增加，21世紀(jì)末世界人口將達(dá)到300億。然而，生物學(xué)家普遍認(rèn)為，地球的容納量?jī)H為100億。顯然，人類將面臨嚴(yán)重的考驗(yàn)，如何利用如此珍貴的資源維持如此高的人口密度。Glossary

natality出生率

The number of individuals entering the population by reproduction per thousand individuals in the population.mortality 死亡率

The number of individuals leaving the population by death per thousand individuals in the population.exponential growth curve指數(shù)生長(zhǎng)曲線 Pattern of population growth in which greater and greater numbers of individuals are produced during the successive doubling times;the pattern that emerges when the per capita birth rate remains even slightly above the per capita death rate, putting aside the effects of immigration and emigration.carrying capacity 容納量，攜帶量，負(fù)載力

The maximum number of individuals in a population(or species)that can be sustained indefinitely by a given environment.logistic growth curve 邏輯生長(zhǎng)曲線

Pattern of population growth in which a low density population slowly in creases in size, goes through a rapid growth phase, then levels off once the carrying capacity is reached.age structure 年齡結(jié)構(gòu)

Of a population, the number of individuals in each of several or many age categories.population density 種群密度，群體密度

The number of individuals of a population that are living in a specified area or volume.density-dependent factors密度依賴因子，密度制約因子

population-limiting factors that become more effective as the size of the population increases.intraspecific competition種內(nèi)競(jìng)爭(zhēng)

Interaction among individuals of the same species that are competing for the same resources.interspecific competition種間競(jìng)爭(zhēng)

Two-species interaction in which both species can harmed due to overlapping niches.density-independent factors密度無(wú)關(guān)因子，非密度制約因子

Population-controlling factors that are not related to the size of the population increases.allelopathy種間感應(yīng)現(xiàn)象，異種相克相成

A chemical interaction between organisms in which one organism suppresses the germination, growth, or reproduction of the other by releasing toxins into the environment.It occurs particularly between freshwater animals, flowering plants, bacteria, and fungi.survivorship curve 存活曲線，生存曲線

A plot of the age-specific survival of a group of individuals in a given environment, from the time of their birth until the last one dies character displacement特征替換

An alteration of the traits of a species as a result of competition or other interactions with associated species.課后作業(yè)：第一篇閱讀材料

圖書(shū)描述

出版日期: 2005年3月1日

《生物專業(yè)英語(yǔ)》在第1版的基礎(chǔ)上更新了部分較為陳舊的閱讀材料，增加了文獻(xiàn)數(shù)據(jù)庫(kù)檢索網(wǎng)上資源檢索等資料，內(nèi)容涉及面廣，取材新穎，圖文并茂,難易適度，充分反映了現(xiàn)代生物學(xué)的發(fā)展趨勢(shì)。在選擇補(bǔ)充材料時(shí)，著重挑選《生物學(xué)文摘》（BA）、《化學(xué)文摘》（CA）、《科學(xué)引文索引》（SCI）檢索和利用的資料，以期通過(guò)這些內(nèi)容提高學(xué)生專業(yè)學(xué)術(shù)期刊閱讀能力、科技寫(xiě)作能力和文獻(xiàn)檢索水平。內(nèi)容涉及動(dòng)物學(xué)、植物學(xué)、細(xì)胞生物學(xué)、遺傳學(xué)、微生物學(xué)、生態(tài)學(xué)、分子生物學(xué)、生物進(jìn)化、生物信息學(xué)、情報(bào)學(xué)等。書(shū)后附有練習(xí)答案、專業(yè)詞匯和參考文獻(xiàn)。

________________________________________ 基本信息

出版社: 高等教育出版社;第2版(2005年3月1日)

平裝: 302頁(yè)

開(kāi)本: 16開(kāi)

ISBN: 7040161435

條形碼: 9787040161434

商品尺寸: 25.6 x 18.2 x 1.4 cm

商品重量: 422 g

ASIN: B0011AUSE6

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《生物專業(yè)英語(yǔ)》可作為高校生物類專業(yè)英語(yǔ)教材，也可作為從事生物學(xué)、農(nóng)林等研究領(lǐng)域的科學(xué)工作者及參加TOEFL或CRE考試學(xué)生的考前閱讀材料。目錄

Lesson One Inside the Living Cell: Structure andFunction of Internal Cell Parts 1 Glossary 3 Exercises 5 Additional Information 8 1．Names of Chemical Element Symbols Commonly Used 8 2．Mathematical Symbols Commonly Used 8 3．Symbols of Length, Capacity and Weight Commonly Used 9 Reading Comprehension 9 Reading Materials 11 The Construction Of Cells 11 Lesson Two Photosynthesis 15 Glossary 17 Exercises 18 Additional Information 21 How to Write a Report or Paper(I)21 Reading Comprehension 26 Reading Materials 27 How Cells Make ATP 27 Using the Electrons Generated by the Citric Acid Cycle to Make ATP 28 Lesson Three Cellular Reproduction：Mitosis and Meiosis 29 Glossary 31 Exercises 32 Additional Information 35 How to Write a Report or Paper(II)35 Reading Comprehension 41 Reading Materials 42 What is Biology 42 The Value of Biology 43 Biological Problems 43 Lesson Four Foundations of Genetics 45 Glossary 46 Exercises 47 Additional Information 51 Chemical Abstract Service 51 Printed Chemical Abstracts(CA)51 Biochemistry Sections of CA(I)52 Reading Comprehension 55 Reading Materials 56 Genes and Characteristics 56 Environmental Influence on Gene Expression 58 Lesson Five Discovering the Chemical Nature of the Gene 59 Glossary 60 Exercises 62 Additional Information 65 Biochemistry Sections of CA(II)65 Reading Comprehension 68 Reading Materials 69 How is the Information in DNA Reproduced so Accurately? 69 What is the Unit of Hereditary Information? 71 Lesson Six The Origin and Diversity of Life 75 Glossary 77 Exercises 78 Additional Information 81 Abbreviations Used in Journals of Biological Sciences 81 Reading Comprehension 83 Reading Materials 84 Earth as a Stage for Life 84 The Unseen Drama: from Molecules to Cells 86 Lesson Seven Fungi：The Great Decomposers 89 Glossary 91 Exercises 92 Additional Information 95 CAS Standard Abbreviations and Acronyms 95 Nature Guide to Authors(I)98 Reading Comprehension 104 Reading Materials 106 The History and Scope of Microbiology 106 Lesson Eight Animal Development 117 Glossary 119 Exercises 121 Additional Information 124 Nature Guide to Authors（Ⅱ）124 Reading Comprehension 130 Reading Materials 131 Animals 131 Lesson Nine The Origin of species 137 Glossary 139 Exercises 140 Additional Information 143 Nature Guide to Authors(Ⅲ)1 43 A．Nature"s Other Submitted Material 1 43 Reading Comprehension 149 Reading Materials 150 How Species Form 150 Lesson Ten The Ecology of Populations 155 Glossary 157 Exercises 158 Additional Information 161 Nature Guide to Authors(IV)161 B．Presubmission Enquiries 161 C．Nature Online Submissions 162 D．Nature Online Revisions 163 E．Getting Published in Nature 165 Reading Comprehension 170 Reading Materials 172 Behavioral Ecology 172 Lesson Eleven Abstracts in Biological Abstracts 1 79 Additional Information 180 Biological Abstracts 180 How to Use Biological Abstracts 184 HOW to Use the Indexes 185 Abbreviations Often Appeared in Biological Abstracts 189 Lesson Twelve The ISI Web of KnowledgeSM Platform：Current and Future Directions 193 Additional Information 203 Web of Science?(I)203 Lesson Thirteen The Handing of Plant Chromosomes 213 Additional Information 223 Web of Science?(Ⅱ)223 Lesson Fourteen Plant Bioinformatics: from Genome to Phenome 241 Additional Information 247 Web of Science?(III)247 Lesson Fifteen Plant Tissue Culture Techniques 257 Additional Information 272 Web of Science?(IV)272 The ISI? Database：The Journal Selection Process 284 Answers to Exercises 289 Glossary of Biological Terms 297 References 301

第二篇：生物教學(xué)案10-5

第10章 人體內(nèi)的物質(zhì)運(yùn)輸和能量供給

第五節(jié) 人體能量的供給

【學(xué)習(xí)目標(biāo)】

1、說(shuō)出人體內(nèi)能量的供給的過(guò)程。

2、說(shuō)出體溫的概念及體溫變化對(duì)人體的影響。

【知識(shí)要點(diǎn)】

一、人體能量的供給

1、轉(zhuǎn)變成人體的組成物質(zhì)

人體從食物中獲得的能量

（利用氧氣將營(yíng)養(yǎng)物質(zhì)氧化分解釋放能量）

熱價(jià)：蛋白質(zhì)17.15kJ/g，糖類17.15kJ/g，脂肪38.91kJ/g。

能量等于重量乘以熱價(jià)。

二、體溫

1、體溫是指人體內(nèi)部的溫度。

2、測(cè)量體溫的三個(gè)部位：腋窩（36.8℃）、口腔（37.2℃）、直腸（37.5℃）。直腸的溫度最接近真實(shí)體溫。

3、維持體溫的相對(duì)穩(wěn)定，是人體進(jìn)行正常生命活動(dòng)的基礎(chǔ)。

4、“發(fā)熱”在一定范圍內(nèi)是有利的，當(dāng)體溫達(dá)到43℃ 就有生命危險(xiǎn)。

【典型例題】

例

1、下列與人體能源物質(zhì)供給無(wú)直接關(guān)系的系統(tǒng)是（D）

A、消化系統(tǒng)B、循環(huán)系統(tǒng)C、呼吸系統(tǒng)D、內(nèi)分泌系統(tǒng)

例

2、相同質(zhì)量的下列營(yíng)養(yǎng)物質(zhì)中，含有能量最多的是（C）

A、蛋白質(zhì)B、糖類C、脂肪D、維生素

例

3、測(cè)得某男同學(xué)口腔、腋窩和直腸三處的體溫分別是37℃、36.5℃、37.2℃，則最接近他實(shí)際體溫的是（C）

A、36.5℃B、37℃C、37.2℃D、37.5℃

【鞏固練習(xí)】《補(bǔ)充習(xí)題》P45-46。

【學(xué)有所得】通過(guò)本節(jié)課的學(xué)習(xí)，你有哪些收獲?請(qǐng)寫(xiě)下來(lái)1、2、3、

第三篇：感 悟 教 師 人 生

感 悟 教 師 人 生

——也談教師師德

百年大計(jì)教育為本，教育大計(jì)教師為本，教師大計(jì)則師德為本，要培養(yǎng)適合時(shí)代需要的高素質(zhì)人才，教師是否具有良好的道德修養(yǎng)至關(guān)重要。

師德，是一個(gè)古老而永恒的話題。而提到師德，人們也常會(huì)用“靈魂工程師”、“無(wú)私奉獻(xiàn)”、“蠟燭精神”、“為人師表”做為社會(huì)衡量教師的潛標(biāo)尺。知識(shí)經(jīng)濟(jì)時(shí)代對(duì)師德賦予了新的內(nèi)涵。2006年2月20日《中國(guó)教育報(bào)》刊載了郭元祥教授撰寫(xiě)的《感悟“教師人生”》一文，作者談到了“教師之服飾”，認(rèn)為“細(xì)節(jié)決定品質(zhì)，服飾影響人的品位”、“教師服飾無(wú)小事”；談到了“教師之語(yǔ)言”，認(rèn)為教師“優(yōu)美的語(yǔ)言是給學(xué)生的最美的教育享受”、“教師的語(yǔ)言是實(shí)現(xiàn)偉大的教育功能的基本途徑”；談到了“教師之習(xí)慣”，認(rèn)為“好習(xí)慣提升人的品質(zhì)和生活品位，壞習(xí)慣糟蹋人的形象和生活層次”、“教育改革核心價(jià)值的追求，需要的是創(chuàng)新，而不是習(xí)慣”；談到了“教師之微笑”，認(rèn)為“教師微笑著面對(duì)學(xué)生，能給學(xué)生一種寬松的師生交往人際環(huán)境，使學(xué)生感受到教師的理解、關(guān)心、寬容和激勵(lì)”、“教師微笑著面對(duì)同事，校長(zhǎng)微笑著面對(duì)教師，有利于構(gòu)建合作性的同事關(guān)系，有利于營(yíng)造一種積極向上、追求卓越、團(tuán)隊(duì)學(xué)習(xí)的發(fā)展型組織”；作者還談到了“教師之思想”，認(rèn)為“思想有多遠(yuǎn)，我們就能走多遠(yuǎn)”、“一個(gè)有思想的教師一定是學(xué)生喜愛(ài)的教師，一個(gè)有魅力的教師，一個(gè)有精神感召力的教師”；最后，作者談到了“教師之信念”，認(rèn)為教師的核心競(jìng)爭(zhēng)力，“也許就是教師的信念”、“教師的信

念蘊(yùn)含著教師的信誓，教師的激情”、“教師的信念中還包含著責(zé)任與使命、愛(ài)心與真情、堅(jiān)持不懈與持之以恒”。因此我認(rèn)為“教師人生”這個(gè)新的論斷是一種對(duì)師德的新的詮釋。

所謂教師人生，就是不僅僅把教育作為一個(gè)職業(yè)來(lái)看待，而是將教育當(dāng)成自己人生的一個(gè)部分來(lái)對(duì)待，來(lái)體驗(yàn)，來(lái)充實(shí)，來(lái)完成。而這樣以對(duì)待自己的生命的態(tài)度對(duì)待教育，向愛(ài)惜自己的生命一樣珍惜教育事業(yè)的境界，我認(rèn)為正是一種高尚的師德體現(xiàn)。那么，如何使教師人生精彩而有價(jià)值呢？

一、“教師人生需要生命的活力，需要生命的激情，需要生命的靈動(dòng)”

車(chē)爾尼雪夫斯基曾說(shuō)過(guò)這樣一段名言：一個(gè)沒(méi)有受到獻(xiàn)身的熱情所鼓舞的人，永遠(yuǎn)不會(huì)做出什么偉大的事情來(lái)。作為教師，我們不僅需要一顆對(duì)學(xué)生的愛(ài)心，相信“皮格馬利翁效應(yīng)”，給每個(gè)學(xué)生以“象牙姑娘”的期待。我們還需要善于結(jié)合學(xué)生的愛(ài)好和興趣情況，在引導(dǎo)和啟發(fā)下開(kāi)展教育教學(xué)。要有一顆耐心，耐心的等待學(xué)生的進(jìn)步，等待學(xué)生從興趣茫然到對(duì)所學(xué)課程熱愛(ài)的過(guò)程。同時(shí)更要求教師要不斷從生活的感悟中提升自己的人生境界，完善自己的道德情操。

精深的生活感悟可以提升教師的人生境界和道德情操。作為一名教師要能在外界豐富多彩的環(huán)境中給自己留下一個(gè)空間，靜下心來(lái)以自己的方式來(lái)讓自己的生命充實(shí)。煥發(fā)教師人生生命的活力，生命的激情和生命的靈動(dòng)。比如，有的教師就曾這樣感悟到：讀書(shū)依然是她最主要的休閑方式。她讀了一些專業(yè)書(shū)籍，努力勾勒為師者的形象；投身教育科

研，做研究性、有靈氣的教師；重朔師生關(guān)系，做民主型、有魅力的教師；形成自身風(fēng)格，做個(gè)性化、有才情的教師。她還讀了不少閑書(shū)，在文化的浸染中滋養(yǎng)心靈，努力在血液中注入人文關(guān)懷，讓生活中充滿情趣和生機(jī)。她堅(jiān)持讀書(shū)，因?yàn)樗X(jué)得做為一名當(dāng)前社會(huì)環(huán)境下的職業(yè)學(xué)校的教師，決不只是機(jī)械的備課、上課、批改作業(yè)更應(yīng)該結(jié)合當(dāng)前社會(huì)的發(fā)展，為專業(yè)發(fā)展的新需要而廣聞博取，咀嚼經(jīng)典，接受時(shí)尚。

人們總是喜歡把教師看作是“人類靈魂的工程師”，把教育事業(yè)比作是“太陽(yáng)底下最光輝的職業(yè)”，無(wú)形中確定了教師的工作性質(zhì)就是要塑造人的靈魂，又把教師的這種工作推到了崇高與偉大的位置上。而這些都應(yīng)該成為歷史性的認(rèn)識(shí)。因?yàn)榻逃旧砭褪且豁?xiàng)成長(zhǎng)中的事業(yè)，這種成長(zhǎng)，不僅有學(xué)生的，也有教師的。教育，不是知識(shí)的蔓延、思想的傳遞，更不是按一定的模式去生產(chǎn)一種產(chǎn)品。教育，應(yīng)該是一種成長(zhǎng)影響另一種成長(zhǎng)。

二、“教師人生需要感動(dòng)。感動(dòng)自己，感動(dòng)學(xué)生，感動(dòng)家長(zhǎng)，感動(dòng)社會(huì)……”

感動(dòng)是一種情感操練,是一種有益的陶冶，更是繼續(xù)教師人生的一份支持。作為一名職業(yè)學(xué)校的教師，面對(duì)著學(xué)生從做人品德的提升到能主動(dòng)去領(lǐng)悟?qū)I(yè)知識(shí)再到學(xué)生的成功就業(yè)和就業(yè)崗位上的出色表現(xiàn)。我們要不斷的在學(xué)生的改變中感動(dòng)自己。進(jìn)而把這種感動(dòng)化作一份繼續(xù)教師人生的動(dòng)力和行動(dòng)，因?yàn)樾袆?dòng)是感動(dòng)的延伸,是我們盡好責(zé)任、做好教師的關(guān)鍵。在職業(yè)學(xué)校的教育教學(xué)中，很關(guān)鍵的一個(gè)過(guò)程是喚起學(xué)生的學(xué)習(xí)興趣和培養(yǎng)學(xué)生學(xué)習(xí)的堅(jiān)持力。我們要善于發(fā)現(xiàn)學(xué)生的興趣點(diǎn)，然后巧妙的切入。比如，學(xué)生的某項(xiàng)專業(yè)

特長(zhǎng)的粗淺愛(ài)好，青春期學(xué)生的好奇好勝，一次偶然的積極表現(xiàn)等等，都可以讓我們當(dāng)作一個(gè)教育契機(jī)，把學(xué)生表現(xiàn)出來(lái)的一點(diǎn)點(diǎn)積極的傾向演變、擴(kuò)大成真正的興趣進(jìn)而穩(wěn)定成愛(ài)好和繼續(xù)發(fā)展的方向。所以一些豐富的專業(yè)實(shí)踐活動(dòng)，比如，一次外出的表演機(jī)會(huì)，一個(gè)被選為禮儀代表的小事等都可以讓我們來(lái)變成讓學(xué)生感動(dòng)學(xué)生自己的機(jī)會(huì)。而學(xué)生的進(jìn)步更需要家長(zhǎng)的支持和肯定。所以，我們?cè)诟袆?dòng)了學(xué)生的同時(shí)也要?jiǎng)?chuàng)造機(jī)會(huì)讓家長(zhǎng)來(lái)重新認(rèn)識(shí)自己的子女。比如把專業(yè)演出帶到學(xué)生家鄉(xiāng)而帶給家長(zhǎng)的那份感動(dòng)，可以讓我們把在校的一份工作效果擴(kuò)大到無(wú)限。而每一個(gè)職業(yè)學(xué)校的學(xué)生的順利工作和工作崗位的突出成績(jī)，也很好的達(dá)成了職業(yè)教育的社會(huì)責(zé)任。

三、“教師人生需要責(zé)任，需要體驗(yàn)教育的快樂(lè)，感受教育的幸福。”

教師人生需要責(zé)任，要有以一種對(duì)人生負(fù)責(zé)的態(tài)度，對(duì)學(xué)生負(fù)責(zé)、對(duì)家長(zhǎng)負(fù)責(zé)、對(duì)職業(yè)負(fù)責(zé)、對(duì)社會(huì)負(fù)責(zé)。使教師人生成為一種信念?？梢赃@樣說(shuō)，一個(gè)教師具有什么樣的思想，也就注定了他有什么樣的教育人生。現(xiàn)在，對(duì)于很多老師來(lái)說(shuō)，都很難擺脫生存的壓力和物質(zhì)利益的誘惑，因而很少關(guān)注自己的內(nèi)心世界，致使很多人思想逐漸萎靡，靈魂日益空虛，在教育路上只剩下忙忙碌碌的空殼。再加之教育理想與教育現(xiàn)實(shí)之間殘酷的沖突，也讓更多的老師失去了教育的熱情，產(chǎn)生了教育懈怠的思想、出現(xiàn)了教育倦怠的現(xiàn)象。這樣的教育氛圍，又怎能影響學(xué)生具有積極進(jìn)取的人生態(tài)度呢？所以作為我們教師自己，應(yīng)該主動(dòng)地去擺脫這種不良情緒的影響，建立自己樂(lè)觀向上的人生態(tài)度和積極進(jìn)取的教育思想。而要擺脫眼前的困境，走出心靈的低谷，就要像郭元

詳先生所說(shuō)，趕快去讀書(shū)。因?yàn)橹挥凶x書(shū)，才能充實(shí)我們空洞的大腦，豐盈我們單薄的靈魂，還我們健康的人格。我們?cè)谧x書(shū)中才能找回從前的夢(mèng)想，完成真正的自己，用積極的思想譜寫(xiě)出自己瑰麗的教育人生。楊啟亮教授在一次學(xué)術(shù)報(bào)告會(huì)上說(shuō)，教師的職業(yè)境界有四個(gè)層次，一是把教育看成是社會(huì)對(duì)教師角色的規(guī)范、要求；二是把教育看作出于職業(yè)責(zé)任的活動(dòng)；三是把教育看作是出于職業(yè)良心的活動(dòng)；四是把教育活動(dòng)當(dāng)作幸福體驗(yàn)。教育從根本意義上來(lái)說(shuō)，就是以人為本，關(guān)注人的幸福，培養(yǎng)人的生活能力，培養(yǎng)人的幸福能力。教師的最高境界是把教育當(dāng)作幸福的活動(dòng)。幸福的教育需要幸福的教師：有了幸福的教師，才可能有幸福的學(xué)習(xí)，才可能有幸福的學(xué)生。當(dāng)枯燥的概念、專業(yè)的表達(dá)方式被我們的教師用生命的激情去表達(dá)和詮釋的時(shí)候，教育顯得如此的獨(dú)特、美麗。我們?cè)谶@樣的經(jīng)歷中關(guān)注著自己教學(xué)生命的成長(zhǎng)發(fā)展，感受著教育理想的生命活力。那滋味，是快樂(lè)，是滿足，是成就！

師德建設(shè)是當(dāng)前教育工作的熱點(diǎn)，而且也引起了全社會(huì)的廣泛關(guān)注。而師德的標(biāo)準(zhǔn)不是唯一的，每一名教師無(wú)論是將教育當(dāng)作一份事業(yè)或是將教育當(dāng)成人生，通過(guò)師德建設(shè)問(wèn)題的探討，我們每位教師都能認(rèn)真的審視自己的教育經(jīng)歷和行為，對(duì)整個(gè)教師隊(duì)伍的師德?tīng)顩r，對(duì)本人的師德情況引發(fā)思考，提高教師師德的境界。同時(shí)在教師人事制度改革的今天，我們職業(yè)學(xué)校更需要一種與學(xué)校共甘苦、同發(fā)展的“校園精神”！所以在抓師德建設(shè)中，進(jìn)行“愛(ài)?！苯逃矐?yīng)該是一個(gè)重要環(huán)節(jié)。

最后引用我最欣賞的一句教育名言，作為教師人生的最高境界。和同事們共勉：

教育是事業(yè)，事業(yè)的成功在于奉獻(xiàn)； 教育是科學(xué)，科學(xué)的探索在于求真； 教育是藝術(shù)，藝術(shù)的生命在于創(chuàng)新”

第四篇：高三生物教學(xué)案：基因工程

楊衛(wèi)東生物工作室www.aqyz.net/bb

高三生物教學(xué)案：基因工程

班級(jí) 姓名

一、基礎(chǔ)填空：

1、基因工程概念

基因工程又叫 或。它是按照人們的意愿，把一種生物的個(gè)別基因復(fù)制出來(lái)，加以修飾改造，然后放到 的細(xì)胞里，生物的遺傳性狀。

2、基因的操作工具

（1）基因的剪刀—— 一種限制酶只能識(shí)別 特定的核苷酸序列，并在特定的位點(diǎn)切割DNA分子。

（2）基因的針線—— 把兩條DNA末端之間的縫隙“縫合”起來(lái)。

（3）基因的運(yùn)輸工具—— 運(yùn)載體能夠在宿生細(xì)胞中復(fù)制并穩(wěn)定保存，具有多個(gè)限制酶切點(diǎn)，具有標(biāo)記基因。常見(jiàn)的運(yùn)載體有、、等。

3、基因操作的基本步驟

（1）提取目的基因 有兩條途徑： 和。

（2）目的基因與運(yùn)載體結(jié)合 用 酶處理目的基因和運(yùn)載體，而后加入DNA連接酶，使目的基因載入到運(yùn)載體中，形成。（3）將目的基因?qū)胧荏w細(xì)胞 重組DNA導(dǎo)入受體細(xì)胞。

（4）目的基因的檢測(cè)與表達(dá) 根據(jù) 判斷目的基因?qū)肱c否；根據(jù)受體細(xì)胞表現(xiàn)出特定的 判斷目的基因的表達(dá)與否。

二、單選題：

1．下列不屬于獲取目的基因的方法是 A．“鳥(niǎo)槍法” B．轉(zhuǎn)錄法 C．反轉(zhuǎn)錄法 D．根據(jù)已知氨基酸序列合成法 2．下列哪項(xiàng)不是基因工程中經(jīng)常使用的用來(lái)運(yùn)載目的基因的載體

A．細(xì)菌質(zhì)粒

B．噬菌體 C．動(dòng)植物病毒

D．細(xì)菌核區(qū)的DNA 3．（2005·全國(guó)卷Ⅰ·3）鐮刀型細(xì)胞貧血癥的病因是血紅蛋白基因的堿基序列發(fā)生了改變。檢測(cè)這種堿基序列改變必須使用的酶是（）A、解旋酶 B、DNA連接酶 C、限制性內(nèi)切酶 D、RNA聚合酶 4．（2005·全國(guó)卷Ⅲ·5）科學(xué)家通過(guò)基因工程的方法，能使馬鈴薯塊莖含有人奶主要蛋白。以下有關(guān)基因工程的敘述，錯(cuò)誤的是（）A、采用反轉(zhuǎn)錄的方法得到的目的基因有內(nèi)含子

B、基因非編碼區(qū)對(duì)于目的基因在塊莖中的表殼是不可缺少的 C、馬鈴薯的葉肉細(xì)胞可用為受體細(xì)胞

D、用同一種限制酶，分別處理質(zhì)粒和含目的基因的DNA，可產(chǎn)生粘性末端而形成重組DNA分子 5．有關(guān)基因工程的敘述正確的是

A．限制酶只在獲得目的基因時(shí)才用 B．重組質(zhì)粒的形成是在細(xì)胞內(nèi)完成的

C．質(zhì)粒都可作為運(yùn)載體 D．蛋白質(zhì)的結(jié)構(gòu)可為合成目的基因提供資料

6、下列有關(guān)基因工程操作的正確順序是（）①目的基因的檢測(cè)和表達(dá) ②目的基因與運(yùn)載體結(jié)合 ③將目的基因?qū)胧荏w細(xì)胞 ④提取目的基因 A．①②③④ B.④③②① C.④②③① D.③④②①

7．不屬于質(zhì)粒被選為基因運(yùn)載體的理由是（）

A．能復(fù)制

B.有多個(gè)限制酶切點(diǎn)

C．具有標(biāo)記基因 D．它是環(huán)狀DNA 8．有關(guān)基因工程的敘述中，錯(cuò)誤的是（）楊衛(wèi)東生物工作室www.aqyz.net/bb A． DNA連接酶將黏性未端的堿基對(duì)連接起來(lái) B． 限制性內(nèi)切酶用于目的基因的獲得 C． 目的基因須由運(yùn)載體導(dǎo)入受體細(xì)胞 D． 人工合成目的基因不用限制性內(nèi)切酶

9、細(xì)菌常常作為基因工程的受體細(xì)胞，下列理由較充分的是

（）

A．形體微小 B．結(jié)構(gòu)簡(jiǎn)單 C．容易監(jiān)測(cè) D．繁殖速度快

10、基因工程的“四步曲”中未發(fā)生堿基互補(bǔ)配對(duì)的是()A．用鳥(niǎo)槍法分離出抗病毒基因

B．將人的胰島素基因與大腸桿菌質(zhì)粒結(jié)合，形成重組質(zhì)粒 C．將重組質(zhì)粒導(dǎo)入受體細(xì)胞 D．抗病毒基因的表達(dá)

11、基因工程又叫DNA重組技術(shù)，是在分子水平上對(duì)生物的定向改造。以下的敘述中，正 確的是

A．一種限制酶只能識(shí)別一種特定的核苷酸序列 B．基因工程所用的工具酶是限制酶、連接酶和運(yùn)載體 C．限制酶的切口一定是GAATTC堿基序列 D．目的基因就是指重組DNA質(zhì)粒

（）

三、多選題

12．目前常被使用的基因載體有()A．質(zhì)粒

B．噬菌體

C．染色體

D．動(dòng)、植物病毒

13．人們利用基因工程的方法，用大腸桿菌生產(chǎn)人類胰島素，這一過(guò)程涉及到（）A．用適當(dāng)?shù)拿笇?duì)胰島素基因與運(yùn)載體進(jìn)行切割并連接 B．把重組后的DNA分子導(dǎo)入受體細(xì)菌內(nèi)進(jìn)行擴(kuò)增 C．檢測(cè)重組DNA分子是否導(dǎo)入受體細(xì)菌內(nèi)并表達(dá)出性狀 D．篩選出能產(chǎn)生胰島素的“工程菌”

14．科學(xué)家已能運(yùn)用基因工程技術(shù)，讓羊合成并分泌抗體。相關(guān)敘述不正確的是（）A．該技術(shù)將導(dǎo)致定向的變異 B．受精卵是理想的受體細(xì)胞

C．垂體分泌的催乳素能促進(jìn)效應(yīng)B細(xì)胞產(chǎn)生抗體 D．采用鳥(niǎo)槍法法獲得目的基因

15、下列關(guān)于基因工程的說(shuō)法正確的是（）A.基因工程的設(shè)計(jì)和施工都是在分子水平上進(jìn)行的

B.目前基因工程中所有的目的基因都是從供體細(xì)胞直接分離得到的 C.基因工程能使科學(xué)家打破物種界限，定向地改造生物性狀

D.只要檢測(cè)出受體細(xì)胞中含有目的基因，那么目的基因一定能成功地進(jìn)行表達(dá)

四、非選擇題

16．（2005·江蘇生物·38）在植物基因工程中，用土壤農(nóng)桿菌中的Ti質(zhì)粒作為運(yùn)載體．把目的基因重組人Ti質(zhì)粒上的T-DNA片段中，再將重組的T-DNA插入植物細(xì)胞的染色體DNA中。

(1)科學(xué)家在進(jìn)行上述基因操作時(shí)，要用同一種 分別切割質(zhì)粒和目的基因，質(zhì)粒的黏性末端與目的基因DNA片段的黏性末端就可通過(guò) 而黏合。

(2)將攜帶抗除草劑基因的重組Ti質(zhì)粒導(dǎo)入二倍體油菜細(xì)胞，經(jīng)培養(yǎng)、篩選獲得一株有抗除草劑特性的轉(zhuǎn)基因植株。經(jīng)分析，該植株含有一個(gè)攜帶目的基因的T-DNA片段，因此可以把它看作是雜合子。理論 楊衛(wèi)東生物工作室www.aqyz.net/bb 上，在該轉(zhuǎn)基因植株自交F1代中，仍具有抗除草劑特性的植株占總數(shù)的，原因是。

(3)種植上述轉(zhuǎn)基因油菜，它所攜帶的目的基因可以通過(guò)花粉傳遞給近緣物種，造成“基因污染”。如果把目的基因?qū)巳~綠體DNA中，就可以避免“基因污染”，原因是。

17、在藥品生產(chǎn)中，有些藥品如干擾素，白細(xì)胞介素，凝血因子等，以前主要是從生物體的組織、細(xì)胞或血液中提取的，由于受原料來(lái)源限制，價(jià)價(jià)十分昂貴，而且產(chǎn)量低，臨床供應(yīng)明顯不足。自70年代遺傳工程發(fā)展起來(lái)以后，人們逐步地在人體內(nèi)發(fā)現(xiàn)了相應(yīng)的目的基因，使之與質(zhì)粒形成重組DNA，并以重組DNA引入大腸桿菌，最后利用這些工程菌，可以高效率地生產(chǎn)出上述各種高質(zhì)量低成本的藥品，請(qǐng)分析回答：

（1）在基因工程中，質(zhì)粒是一種最常用的，它廣泛地存在于細(xì)菌細(xì)胞中，是一種很小的環(huán)狀 分子。

（2）在用目的基因與質(zhì)粒形成重組DNA過(guò)程中，一般要用到的工具酶 是 和。

（3）將含有“某激素基因”的質(zhì)粒導(dǎo)入細(xì)菌細(xì)胞后，能在細(xì)菌細(xì)胞內(nèi)直接合成“某激素”，則該激素在細(xì)菌體內(nèi)的合成包括 和 兩個(gè)階段。

（4）在將質(zhì)粒導(dǎo)入細(xì)菌時(shí)，一般要用 處理細(xì)菌，以增大。

18、中國(guó)青年科學(xué)家陳炬成功地把人的抗病毒干擾素基因“嫁接”到煙草的DNA分子上，使煙草獲得了抗病毒能力，試分析：

（1）陳炬的“嫁接”技術(shù)稱為_(kāi)__________。

（2）人的基因能接到植物體內(nèi)，其物質(zhì)基礎(chǔ)是__________________________。

（3）煙草有了抗病毒能力，這表明煙草體內(nèi)“嫁接”的基因經(jīng)___________產(chǎn)生了___________。這個(gè)事實(shí)說(shuō)明：人和植物共用一套___________，且蛋白質(zhì)的合成方式__________________。

19.干擾素是治療癌癥的重要藥物，它必須從血中提取，每升人血只能提取0.05 μg，所以價(jià)格昂貴。現(xiàn)在美國(guó)加利福尼亞的基因公司用如下圖的方式生產(chǎn)干擾素，試分析其原理和優(yōu)點(diǎn)。

（1）從人的淋巴細(xì)胞中取出___________，使它同細(xì)菌質(zhì)粒相結(jié)合，然后移植到酵母菌的細(xì)胞里，讓酵母菌__________________。

（2）酵母菌能用___________繁殖，速度很快，能大量生產(chǎn)___________，不但提高了產(chǎn)量，也降低了成本。

（3）酵母菌能產(chǎn)生干擾素，這個(gè)事實(shí)說(shuō)明，人和酵母菌共用一套___________。

19、豇豆對(duì)多種害蟲(chóng)具有抗蟲(chóng)能力，根本原因是豇豆體內(nèi)具有胰蛋白酶抑制劑基因（CpTI基因）?？茖W(xué)家將其轉(zhuǎn)移到水稻體內(nèi)后，卻發(fā)現(xiàn)效果不理想，主要原因是CpTI蛋白質(zhì)的積累量不足。經(jīng)過(guò)在體外對(duì)CpTI基因進(jìn)行了修飾后，CpTI蛋白質(zhì)在水稻中的積累量就得到了提高。修飾和表達(dá)過(guò)程如下圖所示：

楊衛(wèi)東生物工作室www.aqyz.net/bb

請(qǐng)根據(jù)以上材料，回答下列問(wèn)題：

⑴CpTI基因是基因工程中的 基因，“信號(hào)肽”序列及“內(nèi)質(zhì)網(wǎng)滯留信號(hào)”序列的基本組成單位是

，在①過(guò)程中，首先要用

酶切開(kāi)，暴露出

，再用

酶連接。

⑵在轉(zhuǎn)基因過(guò)程中，供體細(xì)胞是

，受體細(xì)胞是

。⑶②過(guò)程稱為。

⑷檢測(cè)修飾后的CpTI基因是否表達(dá)的最好方法是。

基因工程答案

（一）基因工程的基本內(nèi)容

1、基因工程概念

基因工程又叫基因拼接技術(shù)或DNA重組技術(shù)。它是按照人們的意愿，把一種生物的個(gè)別基因復(fù)制出來(lái)，加以修飾改造，然后放到另一種生物的細(xì)胞里，定向地改造生物的遺傳性狀。

2、基因的操作工具

（1）基因的剪刀——限制性內(nèi)切酶 一種限制酶只能識(shí)別一種特定的核苷酸序列，并在特定的位點(diǎn)切割DNA分子。

（2）基因的針線——DNA連接酶 把兩條DNA末端之間的縫隙“縫合”起來(lái)。

（3）基因的運(yùn)輸工具——運(yùn)載體 運(yùn)載體能夠在宿生細(xì)胞中復(fù)制并穩(wěn)定保存，具有多個(gè)限制酶切點(diǎn)，具有標(biāo)記基因。常見(jiàn)的運(yùn)載體有質(zhì)粒，噬菌體、動(dòng)植物病毒等。

3、基因操作的基本步驟

（1）提取目的基因 有兩條途徑：直接分離基因和人工合成基因。

（2）目的基因與運(yùn)載體結(jié)合 用同一限制酶處理目的基因和運(yùn)載體，而后加入DNA連接酶，使目的基因載入到運(yùn)載體中，形成重組DNA。

（3）將目的基因?qū)胧荏w細(xì)胞 重組DNA導(dǎo)入受體細(xì)胞。

（4）目的基因的檢測(cè)與表達(dá) 根據(jù)標(biāo)記基因判斷目的基因?qū)肱c否；根據(jù)受體細(xì)胞表現(xiàn)出特定的性狀判斷目的基因的表達(dá)與否。

二、單選題：BDAAD CDADC A

三、多選題 12ABD 13ABCD 14CD 15AC

四、非選擇題

16．(1)限制性內(nèi)切酶，堿基互補(bǔ)配對(duì)。

(2)3/4，雌雄配子各有1／2含抗除草劑基因；受精時(shí)，雌雄配于隨機(jī)結(jié)合。

(3)原因是 葉綠體遺傳表現(xiàn)為母系遺傳，目的基因不會(huì)通過(guò)花粉傳遞麗在下一代中顯現(xiàn)出來(lái)。

17、（1）基因的運(yùn)載體 DNA 楊衛(wèi)東生物工作室www.aqyz.net/bb（2）限制性內(nèi)切酶 DNA連接酶（3）轉(zhuǎn)錄 翻譯

（4）氯化鈣 細(xì)菌細(xì)胞壁的通透性

18、（1）基因工程（2）人和植物的遺傳物質(zhì)DNA結(jié)構(gòu)基本相同（3）轉(zhuǎn)錄和翻譯 抗干擾素 遺傳密碼 基本相同

19、（1）干擾素基因 合成干擾素（2）出芽生殖 干擾素（3）遺傳密碼

20、⑴目的四種脫氧核苷酸

限制性內(nèi)切酶

黏性末端

DNA連接

⑵豇豆

水稻

⑶轉(zhuǎn)錄 ⑷讓多種害蟲(chóng)食用水稻葉片

第五篇：高三生物教學(xué)案封面

高三生物試題集

班級(jí)：_______________ 姓名：_______________ 把簡(jiǎn)單的事情做到極致便是奇跡

淺談高三生物復(fù)習(xí)方法與技巧

生物學(xué)科屬于自然科學(xué)，也是基礎(chǔ)教育必修的一門(mén)學(xué)科。然而由于受中考與高考指揮棒的影響，一些學(xué)校為了片面追求升學(xué)率，生物學(xué)科的教學(xué)在中學(xué)往往沒(méi)有得到足夠的重視。因?yàn)槌踔猩锊粚儆谥锌伎颇浚S多初中學(xué)校的生物課基本屬于走過(guò)場(chǎng)，往往是在會(huì)考前劃出一定的范圍或指定幾套練習(xí)讓學(xué)生死記硬背。進(jìn)入高中，由于高中生物無(wú)論從知識(shí)的深度還是廣度上，都與初中生物有很大的不同，所以相當(dāng)一部分同學(xué)學(xué)習(xí)生物比較困難。筆者從事高三畢業(yè)班的生物教學(xué)多年，親眼所見(jiàn)一些學(xué)生學(xué)習(xí)生物的被動(dòng)與苦惱。其實(shí)，高三生物復(fù)習(xí)并不是雜亂無(wú)章的，以下是老師們的一些體會(huì)，其中提到的方法和技巧可供同學(xué)們借鑒。

一、幾種錯(cuò)誤認(rèn)識(shí)和做法

1.很多人說(shuō)生物是理科中的文科，學(xué)生物背背書(shū)就行。學(xué)生物，的確要背書(shū)，但如果要真正學(xué)好生物，單靠死記硬背是絕不可能的。

2.有些學(xué)生不重視基礎(chǔ)知識(shí)，上課不喜歡聽(tīng)老師講課，也不愿看書(shū)，更不愿對(duì)教材中基本概念、規(guī)律加以理解，在平時(shí)的課堂上總是一味地忙著做題，希望通過(guò)做題來(lái)熟悉相應(yīng)的知識(shí)點(diǎn)。這種做法其實(shí)是不利于生物成績(jī)?nèi)嫣岣叩摹?/p>

3.部分學(xué)生一進(jìn)入高三的復(fù)習(xí)，就急于做套題(各地模擬題)，其實(shí)這也是不好的。因?yàn)榇藭r(shí)學(xué)生對(duì)知識(shí)的掌握不系統(tǒng)不完整，還不具備做高考模擬題的能力。各地模擬題往往是按高考的標(biāo)準(zhǔn)來(lái)命制的，它對(duì)學(xué)生的能力要求比較高，而我們學(xué)生各方面綜合能力的形成還有一個(gè)過(guò)程。所以，在第一輪復(fù)習(xí)過(guò)程中，最好是跟著老師的進(jìn)度，做相應(yīng)的考點(diǎn)訓(xùn)練。

4.相當(dāng)一部分學(xué)生沒(méi)有養(yǎng)成做題的良好習(xí)慣，喜歡把參考答案放在一邊，只要不會(huì)，馬上就看答案，不愿意更深層次地去思考問(wèn)題。很多學(xué)生題做了一大堆，能力并沒(méi)有提高，就是這個(gè)原因。

二、根據(jù)生物學(xué)科的特點(diǎn)，掌握科學(xué)的學(xué)習(xí)方法

1.掌握規(guī)律。規(guī)律是事物本身固有的本質(zhì)的必然聯(lián)系。生物有自身的規(guī)律，如結(jié)構(gòu)與功能相適應(yīng)，局部與整體相統(tǒng)一，生物與環(huán)境相協(xié)調(diào)，以及生物從簡(jiǎn)單到復(fù)雜、從低等到高等、從水生到陸生的進(jìn)化過(guò)程等。掌握這些規(guī)律將有助于生物知識(shí)的理解與運(yùn)用，如學(xué)習(xí)線粒體就抓結(jié)構(gòu)與功能相適應(yīng)：①線粒體外膜，將其與細(xì)胞周?chē)指糸_(kāi)，使有氧呼吸集中在一定區(qū)域內(nèi)進(jìn)行；②內(nèi)膜向內(nèi)折疊形成嵴，擴(kuò)大了膜面積，有利于與有氧呼吸有關(guān)的酶在其上有規(guī)律地分布，使各步反應(yīng)高效有序地進(jìn)行（有氧呼吸第三階段）；③內(nèi)膜圍成的腔內(nèi)有基質(zhì)，基質(zhì)中也有酶的分布，有酶促反應(yīng)進(jìn)行（有氧呼吸第二階段）；④由于有氧呼吸第一階段不在線粒體中進(jìn)行，因而線粒體是有氧呼吸的主要場(chǎng)所。．．2.突破難點(diǎn)。有些知識(shí)比較復(fù)雜，或是過(guò)于抽象，同學(xué)們學(xué)起來(lái)感到有困難，這時(shí)就應(yīng)化難為易，設(shè)法突破難點(diǎn)。通常采用的方法有以下兩種：

(1)復(fù)雜問(wèn)題簡(jiǎn)單化。生物知識(shí)中，有許多難點(diǎn)存在于生命活動(dòng)的復(fù)雜過(guò)程中，難以全面準(zhǔn)確地掌握，而將復(fù)雜問(wèn)題簡(jiǎn)單化能使知識(shí)一目了然。例如人體體溫的調(diào)節(jié)，我們只要抓住健康人產(chǎn)熱與散熱要達(dá)到動(dòng)態(tài)平衡就很容易掌握要點(diǎn)。產(chǎn)熱的機(jī)制可以有骨骼肌戰(zhàn)栗(收縮)，代謝加強(qiáng)則依賴甲狀腺激素和腎上腺素分泌增加來(lái)調(diào)節(jié)；散熱則與皮膚毛細(xì)血管和汗腺有關(guān)。在分析的過(guò)程中，學(xué)生很容易體會(huì)到體溫的調(diào)節(jié)是一個(gè)神經(jīng)——體液的調(diào)節(jié)過(guò)程。

(2)抽象問(wèn)題形象化。有些知識(shí)，與現(xiàn)實(shí)聯(lián)系少，理解起來(lái)困難。這時(shí)，要盡量借助某種方式，使之與實(shí)際聯(lián)系起來(lái)，便于理解。比如，有絲分裂和減數(shù)分裂的學(xué)習(xí)，一直是一些學(xué)生覺(jué)得非常抽象的。如果我們能以2對(duì)同源染色體為例獨(dú)立畫(huà)出各時(shí)期的圖形，我想關(guān)于圖像的識(shí)別、染色體、染色單體的數(shù)量變化和各時(shí)期主要特征的有關(guān)知識(shí)，應(yīng)該就不在話下了。因此，學(xué)習(xí)生物常常需借助圖形、表格、模型、標(biāo)本、錄像等形象化的手段來(lái)幫助理解一些抽象的知識(shí)。

3.歸納總結(jié)。在生物第一輪的復(fù)習(xí)過(guò)程中，老師一般都是按教材的順序?qū)⒅R(shí)分塊學(xué)習(xí)。但當(dāng)學(xué)完一部分內(nèi)容之后，就應(yīng)該把分散在課本不同章節(jié)的分塊的知識(shí)聯(lián)系起來(lái)，歸納整理成系統(tǒng)的知識(shí)。這樣不僅可以在腦子里形成完整的知識(shí)結(jié)構(gòu)，而且也便于理解和記憶。歸納總結(jié)要做到“三抓”：一抓順序，二抓聯(lián)系，三抓重點(diǎn)。抓順序就是要將各知識(shí)點(diǎn)按照本身的邏輯關(guān)系將其串聯(lián)。抓聯(lián)系就是要掌握各知識(shí)點(diǎn)之間的內(nèi)在聯(lián)系，理清點(diǎn)線的縱橫關(guān)系，由線到面，擴(kuò)展成知識(shí)網(wǎng)絡(luò)。抓重點(diǎn)就是抓主流，進(jìn)行歸納總結(jié)，不能大雜燴，胡子眉毛一把抓。

4.圖表過(guò)關(guān)。生物圖表題是一種難度大，靈活性強(qiáng)，知識(shí)覆蓋面廣，能力要求較高的綜合性試題。特別是非選擇題中的圖表作答題，許多學(xué)生感到十分棘手，這其中除了與基礎(chǔ)知識(shí)不扎實(shí)有關(guān)外，更重要的是沒(méi)有掌握運(yùn)用好一種科學(xué)的思維方法。教材中有大量的圖表，這些圖表在課后復(fù)習(xí)時(shí)應(yīng)很好地利用。我們可以嘗試著先將課本中所有的圖表題過(guò)關(guān)，再結(jié)合參考資料上的圖表題專門(mén)訓(xùn)練。非選擇題生物圖表題的一般解法歸納為“審題、定點(diǎn)、作答”3個(gè)步驟。審題就是要讀懂題目，弄清楚題意。定點(diǎn)就是在審題的基礎(chǔ)上，確定題目所涉及到的課本中的知識(shí)點(diǎn)。作答是在審題、定點(diǎn)的基礎(chǔ)上，做出與題目要求觀點(diǎn)一致的答案，前兩步是對(duì)生物圖表題的分析，此步驟則是對(duì)分析的結(jié)果進(jìn)行說(shuō)明，即進(jìn)行文字表達(dá)，它要求科學(xué)準(zhǔn)確，言簡(jiǎn)意賅，要引導(dǎo)學(xué)生運(yùn)用相關(guān)的專業(yè)術(shù)語(yǔ)來(lái)答題。還要注意文字表達(dá)的角度與題干保持一致，密切相關(guān)，否則就會(huì)出現(xiàn)文不對(duì)題的情況。

5.學(xué)以致用。生物學(xué)是一門(mén)與生產(chǎn)和生活聯(lián)系非常緊密的科學(xué)。我們?cè)趶?fù)習(xí)生物學(xué)知識(shí)時(shí)，應(yīng)該注意理解科學(xué)技術(shù)和社會(huì)（STS）之間的相互關(guān)系，理解所學(xué)知識(shí)的社會(huì)價(jià)值，并且運(yùn)用所學(xué)的生物學(xué)知識(shí)去解釋一些現(xiàn)象、解決一些問(wèn)題。近幾年的廣東高考題越來(lái)越接近生產(chǎn)生活實(shí)際，許多材料選自平常老百姓的日常生活。在命題材料的選擇上，往往以社會(huì)熱點(diǎn)問(wèn)題切入，所以熱點(diǎn)要引起足夠的重視，如生態(tài)農(nóng)業(yè)、環(huán)境污染、能源問(wèn)題、全球氣候問(wèn)題（關(guān)注哥本哈根會(huì)議）等。

三、從小處著手，重視能力培養(yǎng)

1.學(xué)會(huì)“看”

高考題目千變?nèi)f化，但 “題在書(shū)外，理在書(shū)中”。在復(fù)習(xí)中，要認(rèn)真閱讀課本，對(duì)課本的核心知識(shí)要達(dá)到“滾瓜爛熟”的地步。此外還要注意以下幾方面的內(nèi)容，一是旁文即教材旁邊提供的小資料或小問(wèn)題，這些都是對(duì)教材內(nèi)容的補(bǔ)充。在看書(shū)時(shí)加以關(guān)注，一方面有利于拓展知識(shí)面，另一方面有利于把握重點(diǎn)；其次是教材中的插圖，有模型，有坐標(biāo)曲線，也有示意圖，這些不僅是高考直接考察的內(nèi)容，而且也是幫助學(xué)生加強(qiáng)理解的輔助工具；然后是課后的閱讀資料，這部分一般不做考試要求，但是這些課外閱讀資料與正文有一定聯(lián)系，關(guān)注之后有利于幫助學(xué)生理解正文，事實(shí)上，考試題目的背景有時(shí)候也會(huì)采用這些材料。

2.學(xué)會(huì)“聽(tīng)”

聽(tīng)課聽(tīng)什么？要聽(tīng)老師分析本節(jié)課的重點(diǎn)、難點(diǎn)、考點(diǎn)和疑點(diǎn)；聽(tīng)自己在預(yù)習(xí)過(guò)程中所未能理解的內(nèi)容；聽(tīng)老師對(duì)相關(guān)問(wèn)題（或習(xí)題）是如何分析的。不僅要認(rèn)真聽(tīng)，還要做好必要的筆記。筆記如何做也有一定的講究，有些同學(xué)喜歡將老師的板書(shū)一字不漏地記下來(lái)，其實(shí)大可不必。我們只要將老師補(bǔ)充的一些重要的知識(shí)點(diǎn)、結(jié)論做一些筆記，對(duì)于習(xí)題也只需記一些主要的分析過(guò)程，課后再進(jìn)行必要的完善即可；萬(wàn)萬(wàn)不可顧此失彼，因?yàn)槊χ龉P記而忽略了聽(tīng)課。

3.學(xué)會(huì)“說(shuō)”

課堂上對(duì)一些問(wèn)題的分析和解決，不要總是依靠于老師的講。有些同學(xué)習(xí)慣于老師的滿堂灌，不喜歡自己整理知識(shí)和組織語(yǔ)言，這就很難將知識(shí)的理解上升到一定的高度。每一位同學(xué)都應(yīng)該積極思考，我怎么解決這個(gè)問(wèn)題？這種思維方法好嗎？哪種表達(dá)更為準(zhǔn)確？所以在課堂上要敢于大膽表述自己的觀點(diǎn)，提高自己的語(yǔ)言表達(dá)能力。

4.學(xué)會(huì)“練”

對(duì)于某一部分知識(shí)點(diǎn)的掌握情況，光會(huì)聽(tīng)和會(huì)看還不行，還需要通過(guò)一定的習(xí)題來(lái)鞏固。一般建議大家在老師的推薦下選擇合適的復(fù)習(xí)資料，但同學(xué)們?nèi)f萬(wàn)不要陷入“題?！?，要掌握好訓(xùn)練的“度”。在訓(xùn)練過(guò)程中，建議大家準(zhǔn)備一個(gè)錯(cuò)題本，將典型的錯(cuò)題整理到錯(cuò)題集上，做錯(cuò)的題目實(shí)際上是寶貴的資源，能夠提醒你在以后的復(fù)習(xí)中避免出錯(cuò)。

5.學(xué)會(huì)“思”

古語(yǔ)云：“學(xué)而不思則罔，思而不學(xué)則殆”。此言提醒我們?cè)趯W(xué)習(xí)的過(guò)程中要經(jīng)常進(jìn)行反思。其實(shí)，學(xué)習(xí)生物知識(shí)最關(guān)鍵的是學(xué)會(huì)其中的學(xué)科思想和答題方法，學(xué)會(huì)思維。因而，同學(xué)們?cè)诳磿?shū)或做題時(shí)，要多想為什么？是否還有其他的方法或表述？此類習(xí)題有何規(guī)律？在反思中提高自己的生物思維模式和答題能力。

6.學(xué)會(huì)“調(diào)”

整個(gè)高三的復(fù)習(xí)都是緊張有序的，整個(gè)過(guò)程伴隨著大大小小的考試，伴隨著學(xué)校、家庭的期望與個(gè)人價(jià)值的實(shí)現(xiàn)，而最終都要通過(guò)考試體現(xiàn)出來(lái)。高考是對(duì)一個(gè)考生知識(shí)與技能、方法與心理等各項(xiàng)綜合素質(zhì)全方位的考查，要想力挫群雄，六月折桂，除掌握必備的知識(shí)、技能、方法外，心理素質(zhì)也是高考成敗的重要因素之一。要做到在高考時(shí)沉著應(yīng)考，處驚不變，在加強(qiáng)解題訓(xùn)練的同時(shí)，應(yīng)加強(qiáng)心理訓(xùn)練。

總之，高考本身就是一門(mén)綜合的藝術(shù)，需要大家在復(fù)習(xí)過(guò)程中不斷領(lǐng)悟。而生物的學(xué)習(xí)雖無(wú)定法，但有章可循。只要我們遵循認(rèn)知的規(guī)律，善于歸納小結(jié)，看練結(jié)合，用心體會(huì)，就一定能找到一套適合自己的學(xué)習(xí)方法。