IGCSEBiology课本summary.

10: The nature of viruses has been apparent only within the last half century, and the first step on this path of discovery was taken by the Russian botanist Dmitri Lvanovsky in 1892 when he studying the tobacco mosaic disease.Viruses are very small entities, ranging in size from 0.02 to 0.3 microns. Unlike the organisms making up the five taxonomic kingdoms of the living world, viruses are acellular, they don’t consist of cells and conduct energy metabolism-they don’t produce ATP and incapable of fermentation , cellular respiration or photosynthesis. As for these, the questions of the viruses origin arise. Do they represent a primitive ‘nearly living’ stage in the evolution of life? Or are they organisms which have lost all cellular components except the nucleus? Could viruses simply be fragments of genetic material derived from cellular organisms? No one really knows the answers to these questions, but we do know that viruses have been around for a long time, and that almost every form of life is susceptible to viral attack.The basic units of a virus consist of nucleic acid surrounded by a capsid or coat, composed of one or at most a few kinds of proteins. These proteins are so assembled as to give the virion a characteristic shape. As they bud through host cell membranes, many animal viruses also acquire a membrane consisting of lipids and proteins, and many bacterial viruses have specialized ‘tails’made of protein. The viral nucleic acid is usually a single molecule and may be composed of either DNA or RNA, but not both. DNA or RNA can be double-stranded or single-stranded.Viruses are obligate intracellular parasite, that is why they must depend upon specific hosts for their reproduction and development. The cells of animals, plants and bacteria can all serve as hosts to viruses. Animal viruses attach to special sites on the plasma membrane of the host cell and are then taken up by endocytosis. A given virus can infect only those cells that have a receptor site for that virus. After the membrane breaks down, the viral protein capsid is broken down by cellular enzymes before the viral nucleic acid, in addition, the viral nucleic acid serves to direct the synthesis of new capsid protein by the protein-synthesizing system of the host, and the capsid combine with new viral nucleic acid spontaneously; and in due course, the new virions are released by the host cell.Plant viruses and bacteriophages must get through a cell wall as well as the host plasma membrane. Infection of a plant usually results from attack by a virion-laden insect vector. The insect uses its proboscis to penetrate the cell wall, and the virions the escape from the insect into the plant. Bacterial viruses are often equipped with tail assemblies that inject the nucleic acid into the host bacterium while the protein coat remains outside. Once inside the host cell, the virus genes takes over the metabolic machinery of the cell and generate their own.Sometimes, viral DNA does not immediately take control of the host metabolism, but insert itself into the host chromosome and present as ‘silent’ provirus until the host cell is exposed to some environmental insult, such as ultraviolet light or radiation.If the viral nucleic acid is RNA, replication needs special enzymes to make the process of RNA-to-RNA synthesis occurs. Some RNA viruses called retroviruses do not carry outRNA-to-RNA transcription. Instead, their RNA is transcribed into DNA is immediately, this reaction is catalyzed by reverse transcriptase, then newly formed DNA is inserted into host DNA and then transcribed into RNA and at last new viruses are produced.After replication and combination, most viruses are released by lysis of the host cell. But in other cases, like that of the retroviruses, viruses are released by extrusion, a process similar tobudding thereby the virus becomes enveloped in a small piece of cell membrane as it moves out of the cell. Lysis result in the destruction of the cell, but extrusion allows the cell to remain alive and continue to produce new viruses for a long period of time.A common way to classify viruses is to separates them first on the nature of the nucleic acid component (DNA or RNA) and then on whether the nucleic acid in the virion is single-ordouble-stranded. Further levels of classification depend on such factors as the overall shape of the virus and the symmetry of the capsid. Most capsid may be categorized as helical, icosahedral and so on. Another level of categorization is based on the presence or absence of membranous envelope around the virion; still further subdivision relies on capsid size and other criteria.18: Within a cell, energy is needed at every stage to drive the reactions that keep life in normal states. On the earth, almost all the energy that fuels life today comes from the sun and is captured in the process of photosynthesis by plants. Most nonphotosynthetic organisms obtain energy by ingesting photosynthetic organisms or others that have themselves ingested photosynthetic organisms, and the energy stored by photosynthesis is usually released through a process known as respiration. In this chapter, we shall discuss these two processes.Photosynthesis is a logical starting point for our discussion of the basic energy transformation of life. In simple terms photosynthesis consists of the reduction of atmospheric CO2 to carbonhydrate by use of light energy, with an associated release of oxygen from water. This reaction can be summarized by the following generalized equation.Like many other physiological processes, photosynthesis consists of a number of sequential steps:①trapping of light energy by chloroplasts; pigments other than chlorophyll(e.g carotenoids)play an accessory role in photosynthesis by transferring energy to chlorophyll a. ②splitting of water and release of high-energy electrons and o2.③electron transfer leading to generation of chemical energy in the form of ATP and the reducing power as NADPH2.④terminal steps involving expenditure of energy of ATP and the reducing power of NADPH2 to fix CO2 molecules, and finally convert this compounds into more complex carbohydrates, such as sucrose, starch, cellulose and so on.Carbon dioxide is an exceedingly energy-poor compound, whereas carbohydrates isenergy-rich. Photosynthesis, then, converts light energy into chemical energy. In chemical terms, the energy is said to be stored by the addition of one more electron-stores energy in the substance being reduced.Although, photosynthesis can occur in any chlorophyll-containing parts of the plant, leaves that expose the greatest area of green tissue to the light are the principal organs of photosynthesis. Through a microscope it can be seen that the outer surfaces of the leaf have a layer of epidermis, which is covered by waxy layer of cuticle. The region between the upper and lower epidermis constitutes the mesophyll portion of the leaf. The cells of mesophyll contain many chloroplasts, which is the organelles that photosynthesis takes place. The CO2 required for photosynthesis can enter through some holes called stomata between the spaces of mesophyll cell. Chloroplast is bounded by two concentric membrane and a third set of internal membranes that form a series of flattened, interconnected sacs known as thylakoids, where chlorophyll moleculesand most of the electron-transport-chain molecules are located. The light reaction, in which light energy is trapped and converted into chemical energy, takes place on the thylakoid membrane. The dark reaction, in which CO2 is reduced to carbohydrates, occurs in the more fluid stroma that surrounds the thylakoid sacs.19: It is evident that the phenomenon of inheritance and variation is of universal important in the living world. To understand it, we must explore how hereditary material expresses itself in new combinations, and whether principles can be formulated about so complex event. This exploration is the study of the branch of biology known as genetics.Some of the basic concepts of heredity grew out of experiments performed by Gregor Mendel in the mid-1800s. Mendel spent most of his lifetime as a monk in an Austrian monastery and during this time he cultivated garden peas, and did a series of experiments to study inheritance in plants. We now know that owing to his elaborate design, unique technique, Mendel formulated two excellent Laws of Inheritance from his breeding experiments on the garden peas: one is the Law of Segregation, the other is the Law of Independent Assortment.The Law of Segregation emphasize on single traits and it can be stated as follows: the inheritance of each individual trait is determined by hereditary factors (genes), each organism possesses two inheritance factors for each character, when gametes are formed, the two factors separate into separated gametes. An offspring formed by the fusion of two gametes therefore receives one factor for each character from each parent. The Law of Independent Assortment involving two or more traits and states that during gametes formation, when two or more genes are involved in a cross, the alleles of one gene are inherited independently of the alleles of another gene. His great achievement laid a solid foundation for the genetics. In order to further understanding of these two laws, some details can be known either:1.Hereditary traits are controlled by discrete units that pass unchanged from generationto generation. For example, the trait white flower seems to disappear in the F1generation, but reappears on the F2 progeny, and that there are no intermediate colors,only red or white.2.Each trait is produced by two hereditary factors. This is a necessary assumption toaccount for the way in which a trait such as flower color appears in successivegenerations in a predictable ratio.3.When two contrasting hereditary factors are present in an organism, such asred-flower color and white-flower color, only one will be expressed. one will bedominant and the other recessive. In the case of the peas, red-flower color isdominant to white-flower color since only the hereditary character of red shows onthe F1 generation.4.Each parent contributes only one of the hereditary factors to each gamete. Moreover,as a consequence of segregation, equal numbers of gametes each kind are formed.5.when gametes unite at the fertilization, the two hereditary factors are broughttogether. Fertilization is a random union in the sense that equal numbers of thedifferent kinds of gametes are produced and it is a matter of chance how they willpair. This being true it should be possible, on a probability basis, to predict the ratioof various characteristics in the offspring. In the flower color experiment, forexample, the ratio of approximately three red-flowered plants to each white-floweredplant conform the expected or predicted ratio of 3 to 1.Today, Mendel’s theories seem rather obvious in the light of the discovery of DNA, genes, chromosomes and meiosis. But it should be remembered that Mendel did his work before all of these theories. He arrived at his great conclusions purely by reasoning from the patterns of inheritance he detected in his experiments. Of course, we know that a variety of influence, including environment, interaction of one gene with another, can cause the appearancechanges, and a single gene may have multiple effects on explaining the phenomenon of the testimony to the strength of the Mendel’s conclusions.20: we know that when a cell divides it must first duplicate the genetic information contained in its chromosomes, so that each daughter cell receive its own copy from the parental cell, but how the genetic information copied on a molecular level? Since 1928, Frederick Griffith published his experiments on pneumococci, a series of experiments led to the realization that DNA is the genetic material. Soon after then, scientists proposed that the linear order of nucleotides in DNA determines the order of amino acids in polypeptides, and therefore determines the structure and function of proteins. This work is now so well established that it is called the central dogma of molecular biology. The dogma states that the information contained in DNA molecules is transferred to RNA molecules, and then from the RNA molecules the information is expressed in the structure of proteins. A summary of this process is: DNA molecule is known to be composed of two nucleotide chains, each nucleotide are joined by covalent bonds between the sugar of one nucleotide and the phosphate group of the next nucleotide in the sequence. The nitrogenous bases are side groups of the chains, the two chains are held together by hydrogen bonds between nitrogenous bases (adenine=thymine and guanine= cytosine) in opposite directions, then, the ladder like double-chained molecule is coiled into a double helix. During replication, the two chains of the DNA separated, and each chain acts as a template for the synthesis of its new partner according to base pairing principle. This process is much like one might unzip a zipper and then produce two complete double-chained molecules, each identical in base sequence to the mother DNA molecule.The transcription of DNA into RNA begins when the enzyme of RNA polymerase binds to a sequence of nucleotides on the DNA called the promoter. Next, the two strands of DNA are separated, and one strand serves as the template for the formation of a complementary strand of RNA. RNA polymerase moves along the DNA and joins the complementary ribonucleotides to the growing RNA strand, one by one. The enzyme works only in the 3’ to 5’direction on its DNA template, assembling RNA in the 5’ to 3’ direction. This process is much like the replication of DNA, with one important difference. When DNA replication, once begin, usually copies all DNA in the cell, whereas RNA synthesis transcribes only selected proteins of the DNA. When the polymerase reaches a termination signal on the DNA, it leaves the DNA chain, and the RNA also detached.Sine DNA molecules are double-stranded, any section of DNA could, in principle, betranscribed into two different RNA molecules, one complementary to each strand. In practice, only one of the strands is transcribed in any one segment of DNA. The orientation of the promoter indicates which strand is to be transcribed because the promoter reads ‘correctly’ only on that strand. The codes for some genes lie on one DNA strand, and codes for other genes lie on its partner.There are four major stages in protein synthesis:1.activation: each amino acid is first activated by reacting with a molecule of ATP. Theactivated amino acid is then attached to its own particular tRNA molecule with theaid of an enzyme(a synthetase) that is specific for that particular amino acid and thatparticular tRNA molecule.2.initiation: this stage consists of three steps:①mRNA, which carries the informationnecessary to synthesize one protein molecule, attached to the 40s ribosome. ②theanticodon of the first tRNA binds to the codon of the mRNA that represents theinitiation signal. ③the 60s ribosome now combines with 40s body. The 60s bodyhas two binding site: one is P site where the growing peptide chain will bind, theother is A site where the incoming tRNA will bring the next amino acid in.3.elongation: at this point the A site is vacant, and each of the 20 tRNA can come inand try to fit itself in. but only one can be the right anticodon that corresponds to thenext codon on the mRNA. In the next elongation, the whole ribosome moves onecodon along the mRNA. Simultaneously with this move, the dipeptide is translocatedfrom the A site to the P site, while the empties tRNA dissociates and goes back to thetRNA pool to pick up another amino acid. After the translocation, the A site isassociated with the next codon on the mRNA. These elongation steps are repeateduntil the last amino acid is attached.4.termination: after the last translocation, the next codon reads ‘stop’ (UAA,UAG orUGA). No more amino acid can be added. Releasing factors then cleave thepolypeptide chain from the last tRNA in a mechanism not yet fully understood. ThetRNA itself is released from the P site, and the whole mRNA is released from theribosome.23：within multiple-cellular organisms, cells of different tissues divide at very differentrates, this process is strictly controlled so that cells divide only when necessary. Occasionally, however, the genetic control fail, a cell begins to grow and divide without restrain, until its offspring begin to crowed surrounding cells and interfere with tissue functions. The alteration has spawned a tumor. Tumor cells divide not only at a horrendous rate, but not respond to the controls telling them when to stop. They will not stop as long as conditions for growthremain favorable. If the tumor cells remain localized, it is said to be benign. Sometimes,however, a tumor cell can metastasize and then grow and divide in other organs of the body, such tumor cells are said to be malignant, or cancerous by definition. A cancer cell has the following characteristics:1.Almost all cancer cells have an abnormal number of chromosomes.2.Cancer cells tend to have a rather spherical shape, making them more mobile thannormal cells.3.Profound abnormalities in the plasma membrane. Membrane transport andpermeability are amplified. Some proteins at the surface are lost or altered, and newone appears.4.Profound changes in the cytoplasm. The cytoskeleton shrinks, becomesdisorganized, or both. Enzyme activity shifts.5.Abnormal growth and division.6.Diminished capacity for adhesion to substrates. Secretions needed for adhesiondwindle; cells cannot become properly anchored in the parent tissue.Our current understanding of cancer suggests that most cancer arise from a single abnormal cell, but how this cell produced? According to multistep hypothesis, we know that the development of a cancer is a long-term process, and it is a result of several independent genetic mutations occurring in the same cell that convert a normal cell into a malignant cell. These mutations can be caused by mutagenic agents known as carcinogens. Carcinogens include numberous natural and synthetic compounds, X-rays, gamma rays and ultraviolet radiation, which may cause single base changes, deletions, insertions and result in cancerous.Genes that cause cancer are called oncogenes. Research results show that more than fifty oncogenes have now been isolated from a variety of animals. In each case, an identical gene sequence, called a proto-oncogene, has been discovered in the normal DNA of the host animal—and the cells carrying them rarely become cancerous. Proto-oncogenes, which is highly conserved in diverse species, is an inherent parts of vertebrate DNA, and it codes for proteins necessary in normal cell functioning. It may become cancer-causing genes only on those occasions when specific mutations altered its structure or its expression.How oncogene-encoded proteins induce cancer? In normal cells, extracellular signals trigger cell division. At the very least, signaling mechanisms of the pathways controlling division must include the following:①growth factors (molecules that carry growth signals from one cell to another);②signal receptors at the membrane surface of the receiving cell;③molecules that transmit signals from the cell surface to specific targets inside. As to cancerous cells, these mechanism is destroyed, this may be generally foreshadows cell division and then cause it cancerous.24: within the past three decades the ability to alter the genetic characteristics of organisms has been enhanced by the advent of modern recombinant DNA technology. The aim of this technology is to impart some new characteristics or functions to an organism by transferring into its cells the DNA of a different organism. This technology can make an organism obtain desired characteristics or functions in short spans, so it has far-reaching potential and has been widely used in agriculture, medicine and so on. Four basic steps are involved in recombinant DNA technology.First, DNA from the donor organisms is cut into small, manageable pieces. To do this, special enzymes are required, the enzymes that cut DNA are called restriction enzymes, each of which hasthe capability to recognize a specific nucleotide base sequence and to cut each DNA strand whenever the sequence occurs. After cutting, there would be a mixture of DNA segments with‘sticky ends’. Of all these fragments, only one may be of interest.The second step in this technology involves joining the pieces of DNA to a vector that acts as a carrier to transport the gene into a new host cell. There are two types of vectors are commonly used: plasmids and bacteriophages. Plasmids are small, circular DNA molecules in the cytoplasm of bacteria and can replicate independently. The initial procedure is similar by using these two vectors: the donor DNA and ‘vector’ DNA are cut with the same restriction enzyme to create the same sticky ends, then the two types of DNA are mixed, complementary base pairing occurs between the sticky ends, and the ends are joined by ligase. But when bacteriophages act as vectors, some protein are to be added next, the protein then combine with the DNA to form bacteriophages, the bacteriophages then infect other bacterial cells by attaching to the cells and injecting their DNA, and this process is called transduction.Once inside the bacteria, the plasmid or bacteriophage replicates autonomously to produce many copies of itself and the foreign DNA it carries. These copies are sometimes referred to as a gene library. Because thousands of identical copies can be produced, the entire library must be searched to find the one clone that has the desired gene. Generally, there are several techniques, including radioactive probe and specific antibody, are used to solve these problems. When the copies have been identified, the bacteria with the desired gene can be cultured, creating limitless numbers of bacteria.Plasmids and bacteriophages are useful vectors to transport DNA into bacterial cells, but such vectors cannot normally enter eukaryotic cell. How can we do about this next? At present, using microinjection, shotgun procedure or bacterium agrobacterium can insert genes into host cells. Of all these methods, microinjection and shotgun techniques have been successfully used in introducing DNA into plant cell or animal cell. But unfortunately, both two ways have a very low success rate. The bacterium agrobacterium can infects a plant cell efficiently and inserts its plasmids into the host’s chromosomes, but not all plants are susceptible to the crown gall bacterium. So we can select considerable ways to cope with special questions.Of course, it must be remembered that getting the DNA into the cell is only the beginning, so at last, we must use proper control elements to stimulate transcription and allow the host cells to multiple large numbers of descendants, and the descendants are screened to commercially utilize.Although, the recombinant DNA technology seems difficult, genetically engineered plants with herbicide-insect and disease-resistance are come into fruit, and gene transfers to domesticated animals have given us many advantages. Looking towards future, some researchers have suggested using this technology to transfer genes for the fixation of atmospheric nitrogen into crop plants, thus eliminating the need for the application of nitrogenous fertilizers.翻译10：病毒病毒的性质在过去的半个世纪已明显，以及在这一发现道路上的第一步是由俄罗斯植物学家DmitriLvanovsky在1892年时研究的烟草花叶疾病。

Absorption 吸收Accommodation 调节Acid Rain 酸雨Acne 粉刺Active site 活性部位Active transport 主动转运Adaptation 适应Additives 添加剂Adenine 腺口票呤Amylase 淀粉酶Anemia 贫血症Angina 心绞痛Angiosperm 被子植物Anopheles 疟蚊Anorexia 厌食Antagonistic pair 相互拮抗的Anther 花粉囊Antibiotic 抗生素Antibody 抗体Monoclonal 单克隆Antigen 抗原Antiseptic 防腐剂Aorta 主动脉Aphid 蚜虫Coronary Artery 冠状动脉Hepatic Artery 肝动脉Pulmonary Artery 肺动脉Renal Artery 肾动脉Arthritis 关节炎Arthropod 节肢动物Artificial selection 人工选择Athlete,s foot 脚气Atmosphere 大气ATP(Adenosine triphosphate) 三磷酸腺甘Atrium 心房Autotroph 自养生物Axes 轴Axon 轴突Bactericide 杀菌剂Bacteriostatic 抑菌剂Bacterium 细菌Base pair 碱基对Bee 蜜蜂Bicarbonate indicator 碳酸氢盐指示剂Biceps 二头肌Bile 胆汁Biogas 沼气Biological control 生物防治Bioreactor 生物反应器Bladder 膀胱Blind spot 盲点Red blood cell 红细胞white blood cell 白细胞BOD ( Biological Oxygen Demand) 生物耗氧Caffeine 咖啡因Calcium 钙Cambium 形成层(植)Bladder cancer 膀胱癌Colon cancer 结结肠癌Lung cancer 肺癌Skin cancer 皮肤癌Cap (Diaphragm) 子宫帽Capillary 毛细血管Carbohydrate 糖类Carbon cycle 碳循环Carbon dioxide 二氧化碳Carnivore 肉食动物Carrier proteins 转运蛋白Carrier 转运者，载体Carrying capacity 转运能力Cartilage 软骨Catalyst催化剂 Cell division 细胞分裂植物前卫细胞壁 植物纤维 着丝粒 小脑Cellulose cell wallCelluloseCentromereCerebellumCerebral cortex大脑皮层Cervix 子宫颈CFC (Chlorofluorocarbon 含氯氟烃Chlorophyll Chloroplast Cholesterol Choroid Chromatid Chromosome Ciliary muscle Cirrhosis Clinistix叶绿素叶绿体胆固醇脉络膜染色单体染色体睫状肌肝硬化尿糖试纸cobalt chloride paper 氯化钻试纸coil 避孕环color blindness combustion community cone cell constipation consumer色盲燃烧群落视锥细胞便秘cornea cotyledon cuticle cystic fibrosis cytoplasm cytosine DDT消费者角膜子叶表皮囊性纤维化细胞质胞嘧啶滴滴涕（杀虫剂的一种）Deamination Decomposition Denaturation 去氨基分解腐烂变性double helix 双螺旋Down ’s syndrome 唐氏综合症drugs 药物ecology 生态学ecosystem 生态系统egg 卵细胞embryo 胚胎emphysema 肺气肿endocrine gland 内分泌腺endonuclease 核酸内切酶endosperm 胚乳endothermy 温血状态，体温的生理调节 energy 能量environmental resistance 环境的阻力enzyme 酶epidermis 表皮epididymis 附寸睾eutrophication 富营养作用excretion 排泄，分泌factor-8 因子8 （血友病的凝血因子） fair testing 客观的实验fermentation 发酵fermenter 发酵器denitrificationdepression diabetes dialysis diaphragm diarrhea adequate diet balanced diet diffusion digestion diploid disease DNA dominant脱氮作用 抑郁 糖尿病透析横膈膜腹泻足量饮食平衡饮食扩散 消化二倍体疾病脱氧核糖核酸显性fern 蕨类植物fertilization 受精fertilizer 肥料fever 发热fiber 纤维fibrin 纤维蛋白fibrinogen 纤维蛋白质filament 细丝fish farming 养鱼业flaccidity 软弱，枯萎fetus 胚胎food chain 食物链food preservation 食物保存fossil fuel 矿物燃料fruit 果实fUngus 真菌，菌类gall bladder 月旦囊gamete 酉己子gene probe 基因探针gene transfer 转基因gene vector 基因载体gene 基因genus 类，属geotropism 向地性global warming 全球变暖glucagon 胰高血糖素glucose 葡萄糖glycogen 糖原gonorrhea 淋病Graafian follicle 格拉夫卵泡，囊状卵泡graphs 线图greenhouse effect 温室效应grey and white matter 灰质和白质guanine 鸟口票吟gut 消化道，内脏habitat 栖息地hemoglobin 血红蛋白hemophilia 血友病haploid 单倍体的hay fever 花粉热，干草热heat 热度，热量hepatitis 肝炎herbicide 除草剂herbivore 食草类动物heroin 海洛因heterotroph 异养生物heterozygous 咋合的homeostasis 平衡状态，稳态homologous pair 同源染色体对homozygous 纯合子的，同型结合的hormone 荷尔蒙horticulture 园艺human growth hormone 人类生长激素humerus 肱骨humidity 潮湿的，温度Huntington,s disease 杭廷顿氏舞蹈病hybridoma 杂交瘤hydrochloric acid 盐酸hyperglycemia 多糖症，高血糖症hypoglycemia 低血糖hypothalamus 丘脑下部hypothermia 体温过低hypothesis 假设active 主动passive 被动natural 天然artificial immunity 人工免疫independent assortment 自由组合，独立分配influenza 流行性感冒insect 昆虫insecticide 杀虫剂Uinsulin 胰岛素iron 铁irradiation 放射，照射IUD (intra-uterine device ) 子宫内器件joint 关节karyotype 染色体组型key 关键kidney 肾脏kingdom 界，王国kwashiorkor 夸休可尔症，恶性营养不良lacteal 乳汁lactic acid 乳酸large intestine 大肠lead 铅leaf 树叶lens 晶体ligament 韧带ligase 连接酶light 光照limewater 石灰水limiting factor 限制因素Linnaeus 林奈lipase 脂肪酶lipid 脂类liver 肝脏loop of Henle 亨利氏襻louse 虱子LSD 麦角酸二乙基酰胺(致幻药)lung 肺lymphocyte 淋巴细胞lysozyme 溶菌酶magnesium 镁malnutrition 营养不良mammal 哺乳动物mammary gland 乳腺marasmus 消瘦，衰弱medulla 脊髓meiosis 减数分裂Mendel,s law孟德尔遗传定律meninges 脑膜meningitis 脑膜炎menstrual cycle 月经周期menstruation 月经meristem 分裂组织，生长点mesophyll 叶肉metabolism 新陈代谢methane 沼气，甲烷microorganism 微生物micropyle 珠孑1mineral ions 矿物离子mitochondria 线粒体mitosis 有丝分裂moss 苔藓mould 霉菌mouth 口腔movement 运动muscle 肌肉mutagen 诱变剂mutation 突变myelin sheath 髓鞘natural selection 自然选择negative feedback 负反馈nephron 肾单位nervous system 神经系统neuron 神经元neurotransmitter 神经递质night blindness 夜盲nitrate 硝酸盐nitrification 硝化作用nitrogen fixation 固氮作用nitrogen cycle 氮循环nitrogen 氮气node of Ranvier 郎飞氏结nucleotide 核苷nucleus 细胞核obesity 肥胖esophagus 食道estrogen 雌激素oil 油optic nerve 视神经osmosis 渗透osteoporosis骨质疏松ovary 卵巢，子房oviduct 输卵管ovulation ovule 胚珠oxygen debt 氧债oxygen 氧ozone 臭氧painkiller 止痛药pancreas 胰腺parasite 寄生虫pasteurization 巴氏灭菌法pathogen 病原体penicillin 青霉素penis 阴茎pepsin 胃蛋白酶peristalsis 蠕动pest 害虫pesticide 杀虫齐U petal 花瓣PH 氢离子浓度phagocyte 吞噬细胞phenotype 显型pheromone 信息素phloem 韧皮部phosphate 磷酸盐photosynthesis 光合作用phototropism 趋光性Pill 口服避孕药pituitary hormones 脑垂体placenta 胎盘pulmonary 肺的radiation 放射radiotherapy 放射治疗radius 镭receptacle 容器，花托recessive 隐性的rectum 直肠reflex action 反射动作reflex arc 反射弧refrigeration 冷藏，制冷rennin 高血压蛋白酶，肾素reptile 爬行动物resistance 抵抗力，阻力respiration 呼吸aerobic respiration 需氧呼吸anaerobic respiration 厌氧呼吸respirometer 呼吸计restriction enzyme 限速酶retina 视网膜rhizobium 根瘤菌ribosome 核糖体rickets 软骨病，佝偻rod cell 视杆细胞root 根root nodule 根瘤roughage 粗粮：Salmonella 沙门氏菌属saprotroph 腐生菌schizophrenia 精神分裂症SCP ( single cell protein) 单细胞蛋白质scrotum 阴囊scurvy 坏血症seed 种子selective breeding 选择育种sepal 萼片sewage 废水，污水sex 性别shiver 颤抖sickle cell anemia 镰状细胞血症skeleton 骨骼skin 皮肤sludge 泥浆，污泥small intestine 小肠smoke 吸烟solvent abuse 溶剂滥用species 种类，类型sperm 精子spermicide 杀精剂U sphincter 括约肌spider 蜘蛛spinal cord 脊索sporulation 抱子形成stamen 雄蕊starch 淀粉stem 茎，干sterilization 灭菌，消毒stigma （花的）柱头stomach 胃stomata 口，气孔style 花柱sucrose 蔗糖surrogacy 代理sweating 排汗synapse 突触synovial fluid 骨膜液，关节液tables 表格tendon 腱testis 睾丸testosterone 睾酮，睾丸素thymine 胸腺嘧啶tobacco 烟草tooth decay 龋齿toxin 毒素transcription 转录transgenic organism 转基因生物体translation 翻译，转换transpiration 蒸发，蒸腾作用transplant 移植triceps 三头肌turgidity 肿胀，浮肿typhoid 伤寒ulna 尺骨umbilical cord 脐带unit 单位urea 尿素ureter 输尿管urethra 尿道uterus 子宫vaccine 疫苗vacuole 液泡vagina 阴道，叶鞘valve 心瓣膜variable 变量，变数vas deferens 输精管vascular bundle 维管束vasectomy 输精管切除术vasoconstriction and vasodilation 血管收缩和舍予张vegetative propagation 无性繁殖vein 静脉hepatic portal vein 肝门静脉umbilical vein 脐静脉vena cava 腔静脉ventricle 心室vesicle （器官的）囊，泡villus 绒毛vinegar 醋剂，醋virus 病毒vitamins 维生素vulva 女阴water potential 水势能water 水weed killer 除草剂wilting 萎蔫X chromosome 乂染色体xylem 木质部Y chromosome Y 染色体yeast 酵母yellow spot 黄斑zygote 受精卵。

生物高一知识点归纳英文版Biology Knowledge Summary for High School FreshmenIntroductionBiology, as a scientific discipline, explores the study of life in all its diverse forms. Understanding and gaining knowledge of biological concepts is essential for high school freshmen embarking on their journey in the field of science. In this article, we will explore the fundamental concepts and principles of biology that form the foundation of a high school biology curriculum.Cellular Level: The Building Blocks of LifeThe cell is the basic unit of life, where all biological processes occur. It consists of various components, including the cell membrane, nucleus, and organelles. The cell membrane regulates the movement of substances in and out of the cell, while the nucleus contains the genetic material - DNA. Organelles like mitochondria, responsible for energy production, and chloroplasts, involved in photosynthesis, play crucial roles in cellular function.Genetics: The Inheritance of TraitsGenetics is the study of heredity and the passing of traits from parents to offspring. It is centered around the molecule known as DNA, which carries genetic information. Genes, segments of DNA, determine specific traits. Through processes such as meiosis and fertilization, genetic information is passed on and leads to genetic variation.Evolution: The Mechanism of Biological DiversityEvolution is the change in heritable traits of populations over successive generations. It is driven by natural selection, where favorable traits increase an organism's chances of survival and reproduction. Charles Darwin's theory of evolution by natural selection revolutionized biology. It explains how diverse species arose from a common ancestor, through adaptations to environmental conditions.Ecology: Interactions in the Natural WorldEcology studies the relationships between organisms and their environment. It encompasses concepts like ecosystems, food chains, and the flow of energy through ecosystems. Biotic factors, such asother organisms, and abiotic factors, such as temperature and soil composition, influence the distribution and abundance of life. Conservation biology and environmental awareness are key components of modern ecological studies.Human Anatomy and Physiology: Understanding Our BodiesThe human body is a complex organism consisting of various systems that work together to maintain homeostasis. The respiratory system allows for gas exchange, while the circulatory system transports oxygen and nutrients throughout the body. The digestive system breaks down food and absorbs nutrients, and the nervous system coordinates bodily functions. Understanding human anatomy and physiology is crucial for understanding how our bodies function and respond to stimuli.Microorganisms: The Unseen WorldMicroorganisms, such as bacteria and viruses, are microscopic organisms that play significant roles in the natural world. They can be beneficial, such as the bacteria in our gut aiding digestion, or harmful, causing diseases. The study of microorganisms, microbiology, iscrucial in understanding their impact on health, agriculture, and the environment.ConclusionBiology encompasses a wide range of fascinating knowledge, from the intricate workings of cells to the complexities of ecological interactions. This brief summary touches upon the key concepts that high school freshmen can expect to explore in their biology classes. By gaining a solid foundation in these fundamental concepts, students can develop a deeper appreciation and understanding of the living world around them.。

Absorption 吸收Accommodation 调节Acid Rain 酸雨Acne 粉刺Active site 活性部位Active transport 主动转运Adaptation 适应Additives 添加剂Adenine 腺嘌呤Amylase 淀粉酶Anemia 贫血症Angina 心绞痛Angiosperm 被子植物Anopheles 疟蚊Anorexia 厌食Antagonistic pair 相互拮抗的Anther 花粉囊Antibiotic 抗生素Antibody 抗体Monoclonal 单克隆Antigen 抗原Antiseptic 防腐剂Aorta 主动脉Aphid 蚜虫Coronary Artery 冠状动脉Hepatic Artery 肝动脉Pulmonary Artery 肺动脉Renal Artery 肾动脉Arthritis 关节炎Arthropod 节肢动物Artificial selection 人工选择Athlete’s foot 脚气Atmosphere 大气ATP(Adenosine triphosphate) 三磷酸腺苷Atrium 心房Autotroph 自养生物Axes 轴Axon 轴突Bactericide 杀菌剂Bacteriostatic 抑菌剂Bacterium 细菌Base pair 碱基对Bee 蜜蜂Bicarbonate indicator 碳酸氢盐指示剂Biceps 二头肌Bile 胆汁Biogas 沼气Biological control 生物防治Bioreactor 生物反应器Bladder 膀胱Blind spot 盲点Red blood cell 红细胞white blood cell 白细胞BOD（Biological Oxygen Demand）生物耗氧Caffeine 咖啡因Calcium 钙Cambium 形成层（植）Bladder cancer 膀胱癌Colon cancer 结结肠癌Lung cancer 肺癌Skin cancer 皮肤癌Cap（Diaphragm）子宫帽Capillary 毛细血管Carbohydrate 糖类Carbon cycle 碳循环Carbon dioxide 二氧化碳Carnivore 肉食动物Carrier proteins 转运蛋白Carrier 转运者，载体Carrying capacity 转运能力Cartilage 软骨Catalyst 催化剂Cell division 细胞分裂Cellulose cell wall 植物前卫细胞壁Cellulose 植物纤维Centromere 着丝粒Cerebellum 小脑Cerebral cortex 大脑皮层Cervix 子宫颈CFC（Chlorofluorocarbon 含氯氟烃Chlorophyll 叶绿素Chloroplast 叶绿体Cholesterol 胆固醇Choroid 脉络膜Chromatid 染色单体Chromosome 染色体Ciliary muscle 睫状肌Cirrhosis 肝硬化Clinistix 尿糖试纸cobalt chloride paper 氯化钴试纸coil 避孕环color blindness 色盲combustion 燃烧community 群落cone cell 视锥细胞constipation 便秘consumer 消费者cornea 角膜cotyledon 子叶cuticle 表皮cystic fibrosis 囊性纤维化cytoplasm 细胞质cytosine 胞嘧啶DDT 滴滴涕（杀虫剂的一种）Deamination 去氨基Decomposition 分解腐烂Denaturation 变性denitrification 脱氮作用depression 抑郁diabetes 糖尿病dialysis 透析diaphragm 横膈膜diarrhea 腹泻adequate diet 足量饮食balanced diet 平衡饮食diffusion 扩散digestion 消化diploid 二倍体disease 疾病DNA 脱氧核糖核酸dominant 显性double helix 双螺旋Dow n ’s syndrome 唐氏综合症drugs 药物ecology 生态学ecosystem 生态系统egg 卵细胞embryo 胚胎emphysema 肺气肿endocrine gland 内分泌腺endonuclease 核酸内切酶endosperm 胚乳endothermy 温血状态，体温的生理调节energy 能量environmental resistance 环境的阻力enzyme 酶epidermis 表皮epididymis 附睾eutrophication 富营养作用excretion 排泄，分泌factor-8 因子8 （血友病的凝血因子）fair testing 客观的实验fermentation 发酵fermenter 发酵器fern 蕨类植物fertilization 受精fertilizer 肥料fever 发热fiber 纤维fibrin 纤维蛋白fibrinogen 纤维蛋白质filament 细丝fish farming 养鱼业flaccidity 软弱，枯萎fetus 胚胎food chain 食物链food preservation 食物保存fossil fuel 矿物燃料fruit 果实fungus 真菌，菌类gall bladder 胆囊gamete 配子gene probe 基因探针gene transfer 转基因gene vector 基因载体gene 基因genus 类，属geotropism 向地性global warming 全球变暖glucagon 胰高血糖素glucose 葡萄糖glycogen 糖原gonorrhea 淋病Graafian follicle 格拉夫卵泡，囊状卵泡graphs 线图greenhouse effect 温室效应grey and white matter 灰质和白质guanine 鸟嘌吟gut 消化道，内脏habitat 栖息地hemoglobin 血红蛋白hemophilia 血友病haploid 单倍体的hay fever 花粉热，干草热heat 热度，热量hepatitis 肝炎herbicide 除草剂herbivore 食草类动物heroin 海洛因heterotroph 异养生物heterozygous 咋合的homeostasis 平衡状态，稳态homologous pair 同源染色体对homozygous 纯合子的，同型结合的hormone 荷尔蒙horticulture 园艺human growth hormone 人类生长激素humerus 肱骨humidity 潮湿的，温度Huntingto n’s disease 杭廷顿氏舞蹈病hybridoma 杂交瘤hydrochloric acid 盐酸hyperglycemia 多糖症，高血糖症hypoglycemia 低血糖hypothalamus 丘脑下部hypothermia 体温过低hypothesis 假设active 主动passive 被动natural 天然artificial immunity 人工免疫independent assortment 自由组合，独立分配influenza 流行性感冒insect 昆虫insecticide 杀虫剂insulin 胰岛素iron 铁irradiation 放射，照射IUD（intra-uterine device）子宫内器件joint 关节karyotype 染色体组型key 关键kidney 肾脏kingdom 界，王国kwashiorkor 夸休可尔症，恶性营养不良lacteal 乳汁lactic acid 乳酸large intestine 大肠lead 铅leaf 树叶lens 晶体ligament 韧带ligase 连接酶light 光照limewater 石灰水limiting factor 限制因素Linnaeus 林奈lipase 脂肪酶lipid 脂类liver 肝脏loop of Henle 亨利氏襻louse 虱子LSD 麦角酸二乙基酰胺（致幻药）lung 肺lymphocyte 淋巴细胞lysozyme 溶菌酶magnesium 镁malnutrition 营养不良mammal 哺乳动物mammary gland 乳腺marasmus 消瘦，衰弱medulla 脊髓meiosis 减数分裂Mende l’s law孟德尔遗传定律meninges 脑膜meningitis 脑膜炎menstrual cycle 月经周期menstruation 月经meristem 分裂组织，生长点mesophyll 叶肉metabolism 新陈代谢methane 沼气，甲烷microorganism 微生物micropyle 珠孔mineral ions 矿物离子mitochondria 线粒体mitosis 有丝分裂moss 苔藓mould 霉菌mouth 口腔movement 运动muscle 肌肉mutagen 诱变剂mutation 突变myelin sheath 髓鞘natural selection 自然选择negative feedback 负反馈nephron 肾单位nervous system 神经系统neuron 神经元neurotransmitter 神经递质night blindness 夜盲nitrate 硝酸盐nitrification 硝化作用nitrogen fixation 固氮作用nitrogen cycle 氮循环nitrogen 氮气node of Ranvier 郎飞氏结nucleotide 核苷nucleus 细胞核obesity 肥胖esophagus 食道estrogen 雌激素oil 油optic nerve 视神经osmosis 渗透osteoporosis 骨质疏松ovary 卵巢，子房oviduct 输卵管ovulation ovule 胚珠oxygen debt 氧债oxygen 氧ozone 臭氧painkiller 止痛药pancreas 胰腺parasite 寄生虫pasteurization 巴氏灭菌法pathogen 病原体penicillin 青霉素penis 阴茎pepsin 胃蛋白酶peristalsis 蠕动pest 害虫pesticide 杀虫剂petal 花瓣PH 氢离子浓度phagocyte 吞噬细胞phenotype 显型pheromone 信息素phloem 韧皮部phosphate 磷酸盐photosynthesis 光合作用phototropism 趋光性Pill 口服避孕药pituitary hormones 脑垂体placenta 胎盘pulmonary 肺的radiation 放射radiotherapy 放射治疗radius 镭receptacle 容器，花托recessive 隐性的rectum 直肠reflex action 反射动作reflex arc 反射弧refrigeration 冷藏，制冷rennin 高血压蛋白酶，肾素reptile 爬行动物resistance 抵抗力，阻力respiration 呼吸aerobic respiration 需氧呼吸anaerobic respiration 厌氧呼吸respirometer 呼吸计restriction enzyme 限速酶retina 视网膜rhizobium 根瘤菌ribosome 核糖体rickets 软骨病，佝偻rod cell 视杆细胞root 根root nodule 根瘤roughage 粗粮Salmonella 沙门氏菌属saprotroph 腐生菌schizophrenia 精神分裂症SCP（single cell protein）单细胞蛋白质scrotum 阴囊scurvy 坏血症seed 种子selective breeding 选择育种sepal 萼片sewage 废水，污水sex 性别shiver 颤抖sickle cell anemia 镰状细胞血症skeleton 骨骼skin 皮肤sludge 泥浆，污泥small intestine 小肠smoke 吸烟solvent abuse 溶剂滥用species 种类，类型sperm 精子spermicide 杀精剂sphincter 括约肌spider 蜘蛛spinal cord 脊索sporulation 孢子形成stamen 雄蕊starch 淀粉stem 茎，干sterilization 灭菌，消毒stigma （花的）柱头stomach 胃stomata 口，气孔style 花柱sucrose 蔗糖surrogacy 代理sweating 排汗synapse 突触synovial fluid 骨膜液，关节液tables 表格tendon 腱testis 睾丸testosterone 睾酮，睾丸素thymine 胸腺嘧啶tobacco 烟草tooth decay 龋齿toxin 毒素transcription 转录transgenic organism 转基因生物体translation 翻译，转换transpiration 蒸发，蒸腾作用transplant 移植triceps 三头肌turgidity 肿胀，浮肿typhoid 伤寒ulna 尺骨umbilical cord 脐带unit 单位urea 尿素ureter 输尿管urethra 尿道uterus 子宫vaccine 疫苗vacuole 液泡vagina 阴道，叶鞘valve 心瓣膜variable 变量，变数vas deferens 输精管vascular bundle 维管束vasectomy 输精管切除术vasoconstriction and vasodilation 血管收缩和舒张vegetative propagation 无性繁殖vein 静脉hepatic portal vein 肝门静脉umbilical vein 脐静脉vena cava 腔静脉ventricle 心室vesicle （器官的）囊，泡villus 绒毛vinegar 醋剂，醋virus 病毒vitamins 维生素vulva 女阴water potential 水势能water 水weed killer 除草剂wilting 萎蔫X chromosome X染色体xylem 木质部Y chromosome Y染色体yeast 酵母yellow spot 黄斑zygote 受精卵。

高中生物教案英语笔记大学Subject: BiologyGrade: High SchoolTopic: Cell Structure and FunctionObjective: Students will be able to identify the different organelles within a cell and understand their functions.Materials:- Textbook- Diagrams of cell structure- Interactive online resources- Microscopes (optional)Procedure:1. Introduction (10 minutes)- Begin the lesson by discussing the importance of cells in living organisms. Ask students to brainstorm what they already know about cells.2. Cell Theory (10 minutes)- Explain the three parts of the cell theory: all living organisms are composed of one or more cells, the cell is the basic unit of life, and all cells come from pre-existing cells. Discuss how this theory was developed over time.3. Cell Structure (20 minutes)- Show students diagrams of a typical plant and animal cell. Point out the different organelles such as the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. Discuss the function of each organelle.4. Cell Function (20 minutes)- Have students work in pairs to research the specific functions of each organelle. They can use their textbooks or online resources to gather information. Afterward, have them present their findings to the class.5. Microscope Demonstration (optional) (15 minutes)- If microscopes are available, take students to the lab and demonstrate how to use the microscopes to observe cells. Have them identify the different organelles they learned about in class.6. Review and Assessment (15 minutes)- Summarize the key points of the lesson and answer any questions students may have. Administer a short quiz to assess their understanding of cell structure and function.7. Extension Activity (Homework)- Assign students a research project on a specific type of cell (e.g., red blood cells, nerve cells). They can create a poster or presentation highlighting the unique features of that cell. Conclusion:By the end of this lesson, students should have a solid understanding of cell structure and function. This foundational knowledge will help them as they continue their studies in biology.。