专业外语复习指南 Microsoft Word 文档.doc

绪论1.If in addition the amino acids is permitted only in amounts that produce a measurable improvement in protein quality，then there is no danger that excess amino acids will be consumed.2.译文：如果允许加入的氨基酸量对蛋白质质量的改善程度是可衡量的，那么就不存在使用过量氨基酸的危险。w This method which is being rapidly developed involves the exposure of food to a cooling medium at a very low temperature.w 译文：这种正处于迅速发展之中的方法，是将食品与温度极低的冷媒直接接触来实现冻结的。w If we do not control the processing conditions，some abnormal phenomena might occur.w 译文：如果我们不控制处理条件，一些不正常的现象就会发生w 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. 后置定语w 这种数量（关系）反映了（如下）事实：核糖体是将氨基酸合成为用于输出或用于细胞活动的蛋白质的场所。w 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. w 两个亚基在合成蛋白质时沿着mRNA链移动，读取其中编码的遗传序列并将其翻译成蛋白质w 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. 被动语态的翻译w 两种类型内质网的作用是将细胞内的特定产物分离，并进而将它们分流到细胞的特定部位或细胞外去。w Within the Golgi complex molecules are modified and packaged for export out of the cell or for delivery elsewhere in the cytoplasm.w 分子在高尔基体中被修饰和折叠，然后输出到细胞外，或者运送到细胞质的其它部分w 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.后置定语w 有一类液泡称为溶酶体，其中含有从高尔基体组装到溶酶体的消化酶，能将大多数生物大分子分解。w It is on the large surface area provided by the inner cristae of mitochondria that ATP-generating enzymes are located.w 线粒体内膜的嵴增大了表面积，合成ATP的酶类就位于其上w Such movements require a solid substrate to which the cell can adhere and can be guided by the geometry of the surface.w 这种运动需要细胞附着在稳固的基底上，并由表面的形状所引导。More complex organisms, including plants and animals, are multicellular; their bodies are cooperatives of many kinds of specialized cells that could not survive for long on their own.包括植物和动物在内的更加复杂的生物都是多细胞（生物）；它们的身体都是多种特化细胞的联合体，（这些细胞）不能长期独立生存。In a light microscope (LM), visible light ispassed through the specimen and then through glass lenses. The lenses refract折射 (bend) the light in such a way that the image of the specimen is magnified as it is projected投射 into the eye, onto photographic film or a digital sensor, or onto a video screen在光学显微镜中，可见光先通过样品，再通过玻璃透镜。透镜将光折射，因而当样品的图像投射到眼睛、照相胶片、数字传感器或者屏幕上时就放大了。A useful technique for studying cell structure and function is cell fractionation, which takes cells apart and separates the major organelles and other subcellular structures from one another. 系表结构细胞分级分离是研究细胞结构和功能的一种很有用的技术，可以将细胞分开并分离主要的细胞器以及其它亚细胞结构。The most obvious function of the cytoskeleton is to give mechanical support to the cell and maintain its shape. This is especially important for animal cells, which lack walls.细胞骨架最显著的功能是为细胞提供机械支持并维持其形状。动物细胞由于没有细胞壁，因而这方面对其尤其重要。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.光合作用的光反应（过程）中，吸收（光能的）分子返回基态时，“多余的”激发能转移给其它分子并储存为化学能。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照射到任一色素分子的光能都汇集到一个特殊的叶绿素a分子上，这个分子称为反应中心叶绿素，可直接参与光合作用。This packaging takes place through a series of oxidation-reduction reactions set in motion when light strikes the p680 reaction center in photosystem II. 这种转换从光照射到光系统II的反应中心p680开始，经历一系列氧化还原反应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. 通过光系统II和I（进行）的单向电子流动称为非环式光合磷酸化。植物也可通过环式光合磷酸化获取额外的ATP，这个过程中部分电子经由光系统II和I之间的电子传递链回流。The pigment chlorophyll in plant cells absorbs photons within a particular absorption spectrum - a statement of the amount of light absorbed by chlorophyll at different wavelengths植物细胞的叶绿素吸收光子时具有特定的吸收光谱即叶绿素对不同波长光吸收量的表示方法。第三章 w During prophase, other microtubules, the centromeric fibers, extend outward from the spindle poles to structures on the chromosomes called kinetochores. 在有丝分裂前期另一种微管，着丝粒丝，从纺锤体两极延伸到染色体中称为着丝点的结构上。In animals it is associated with centriole, while in plant and fungal cells spindle formation is associated with regions called microtubule organizing centers在动物中（纺锤体形成）与中心粒有关，而在植物和真菌细胞中则与称为微管组织中心的区域相关。Meiosis is a special form of cell division that takes place in the reproductive organs that produce sex cells. w 减数分裂是一种特殊形式的细胞分裂，发生在产生性细胞的生殖器官中。w （减数分裂是一种发生在产生性细胞的生殖器官中的特殊形式的细胞分裂。）w It is this event that results in the halving of the chromosome number in the fourdaughter cells that result from meiosis. 正是这一事件导致减数分裂产生的四个子细胞的染色体数减半。w The advantages of this type of reproduction are that it preserves the parents successful genetic complement,requires little or no specialization of reproductive organs, and is more rapid than sexual reproduction. 此类生殖方式的优点是能够保持亲代良好的遗传特性，几乎不需要特化的生殖器官，且比有性生殖更加快速。第四章Both of the 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 这两种早期观点均体现了融合理论的看法：来自父母双方的遗传性状融合在一起，使得它们相异的特征在后代中看不到了。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.孟德尔在大学里接触过关于物质粒子性的理论，并且学习过数学。他通过一系列精心设计的实验，展示了遗传的粒子性。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. 从父母双方分别遗传了某一性状的相同等位基因的生物称为该性状的纯合体；若遗传的是某一性状的不同等位基因，则称为该性状的杂合体。 The ratio of dominant phenotypes (if any) in the progeny makes clear whether the unknown genotype is heterozygous, homozygous dominant, or homozygous recessive. 通过后代中显性表型的比例（如果有的话）就能弄清这个未知基因型是杂合体，显性纯合体，还是隐性纯合体。 An apparent exception to Mendels laws is incomplete dominance, a phenomenon in which offspring of a cross exhibit a phenotype that is intermediate between those of the parents. 孟德尔遗传规律的显著例外之一是不完全显性现象，即杂交后代的表现型处于父母表型的中间状态。第五章Nucleic acid,originally isolated by Johann Miescher in 1871, was identified as a prime constituent of chromosome through the use of the red-staining method developed by Feulgen in the early 1900s. 核酸由约翰米歇尔于1871年首次分离获得。20世纪初期，利用孚尔根提出的染色法，人们发现核酸是染色体的主要成分。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. 几乎同时，莱文发现DNA含有4种碱基，每种碱基分别与一分子糖和一个磷酸基团结合，构成莱文称为核苷酸的化合物。 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. 1950年代马萨蔡司和阿尔弗雷德赫尔希研究E. coli时发现，遗传信息的载体是DNA而非蛋白质。这一研究终结了关于DNA能否携带复杂的遗传信息的争论 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. 证据之一是由Linus Pauling提出的，DNA可能形成通过氢键维持的螺旋结构。另一项证据来自Franklin和Wilkins拍摄的DNA X射线衍射照片，其中显示出按一定间隔盘绕的螺旋结构。第六章The Origin and Diversity of Life1. The major current hypothesis holds that life arose spontaneously on the early earth by means of chemical evolution from nonliving substances目前的主流学说认为，生命是在早期地球上通过化学进化由无生命物质自发地产生的。2. Evidence suggests that RNA, which can form spontaneously under conditions mimicking those of the early earth, was the first informational molecule有证据表明，RNA可在模拟早期地球的环境下自发形成，可能是最早的信息分子。3. Following the development of a lipid-protein surface layer and replicating RNAand 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 development of metabolic pathways. 脂-蛋白表层和RNA及DNA信息分子形成之后，导致活细胞出现的其它事件可能包括：遗传密码的起源；RNA或DNA被隔离到类细胞结构中；代谢途径的出现。4. 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. 大气氧浓度的增加也使得好氧细胞和细胞呼吸作用的进化成为可能，进而标志着全球碳循环的起始。第七章Fu