微生物期末英文习题答案.doc

一、CHOICE QUESTIONS：（20 Cent）1. Catabolism is a form of metabolism in which _ molecules are converted into _ molecules. a. large, small c. amino acid, protein b. small, large d. food, storage2. A microbicidal agent has what effect? a. sterilizes b. inhibits microorganisms c. is toxic to human cells d. destroys microorganisms3. Environmental factors such as temperature and pH exert their effect on the _ of microbial cells. a. membranes c. enzymes b. DNA d. cell wall4. In general , fungi derive nutrients through a. photosynthesis c. digesting organic substrates b. engulfing bacteria d. parasitism5. Both flagella and cilia are found primarily in_ a. algae c. fungi b. protozoa d. both b and c 6. Which of the following is not found in all bacterial cells ? a. cell membrane c. ribosomes b. a nucleoid d. capsule7. Pili are tubular shafts in _bacteria that serve as a means of _. a. gram-positive, genetic exchange b. gram-positive, attachment c. gram-negative, genetic exchange d. gram-negative, protection8. Which of the following is a primary bacteria cell wall function ? a. transport c. support b. motility d. adhesion9. A bacterial arrangement in packets of eight cells is described as a _ .a. micrococcus c. tetradb. diplococcus d.sarcina10. Genetic analysis of bacteria would include a. fermentation testingb. ability to digest complex nutrientsc. presence of oxidased. G+C content11. In general, if two haploid cells fuse , _will result . a. a germ cell c. mitosis b. a diploid zygote d. meiosis12. What is embedded in rough endoplasmic reticulum ? a. ribosomes c. chromatin b. Golgi apparatus d. vesicles13. In general , fungi derive nutrients through a. photosynthesis c. digesting organic substrates b. engulfing bacteria d. parasitism14. An organism that can synthesize all its required organic components from CO2 using energy from the sun is a a. photoautotroph c. chemoautotroph b. photoheterotroph d. chemoheterotroph15. An obligate halophile high a. pH c. salt b. temperature d. pressure16. Catabolism is a form of metabolism in which _ molecules are converted into _ molecules. a. large, small c. amino acid, protein b. small, large d. food, storage17. An enzyme a. becomes part of the final products b. is nonspecific for substrate c. is consumed by the reaction d. is heat and pH labile18. Many coenzymes are a. metals c. proteins b. vitamins d. substrates19. The temperature-pressure combination for an autoclave is a. 100 and 4 psi c. 131 and 9 psi b. 121 and 15 psi d. 115 and 3 psi20. The most versatile methods of sterilizing heat-sensitive liquids is a. UV radiation c. beta propiolactone b. exposure d. filtration二、Fill a vacancy：（15 Cents）1. The major locomotor structures in bacteria are flagella .2. A conidium is a/an _ asexal spore , and a zygospore is a/an_ sexal _ spore .3. An organic nutrient essential to an organisms metabolism that cannot be synthesized itself is termed a/an growth factor .4. Active transport of a substance across a membrane requires ATP .5. Superoxide ion is toxic to strict anaerobes because they lack catalase .6. During the _ stationary phase, the rate of new cells being added to the population has slowed down.7. Complete oxidation of glucose in aerobic respiration yields a net output of 38_ ATP.8. Microorganisms have two fundamentally different types of cells-Prokaryotes and Eucaryote and are distributed among several kingdoms or domains.9. Koch developed the techniques required to grow bacteria on solid media and to isolate pure cultures of pathogens.10.Phototrophs capture radiant energy from the sun. Chemoorganotrophs oxidize organic molecules to liberate energy, while chemolithotrophs employ inorganic nutrients as energy sources.11 Mesosomes are internal extensions of the_Cell Wall_ ?1. The major locomotor structures in bacteria are flagella .2. A conidiospores is a/an _ asexal spore , and a zygospore is a/an_ sexal _ spore .3. An organic nutrient essential to an organisms metabolism that cannot be synthesized itself is termed a/an growth factor .4. Active transport of a substance across a membrane requires ATP .6. During the _ stationary phase, the rate of new cells being added to the population has slowed down.7. Microorganisms have two fundamentally different types of cells-Prokaryotes and Eucaryote and are distributed among several kingdoms or domains.8.Yeasts are unicellular fungi , and molds are filamentous _fungi .9/ Ribosomes is embedded in rough endoplasmic reticulum 四、CONCEPT QUESTIONS(55 Cents)1. Describe Kochs postulates. why are they important?(10 Cents)Kochs postulates and can be summarized as follows:1. The microorganism must be present in every case of the disease but absent from healthy organisms.2. The suspected microorganism must be isolated and grown in a pure culture.3. The same disease must result when the isolated microorganism is inoculated into a healthy host.4. The same microorganism must be isolated again from the diseased host.The first direct demonstration of the role of bacteria in causing disease Kochs proof that Bacillus anthracis caused anthrax was independently confirmed by Pasteur and his coworkers. They discovered that after burial of dead animals, anthrax spores survived and were brought to the surface by earthworms. Healthy animals then ingested the spores and became ill.2. Give a simple comparison of transport systems in graph? (10 Cents)ItemsPassive diffusionFacilitated diffusionActive transportGroup translocationcarrier proteins NonYesYesYestransport speedSlow Rapid Rapid Rapid against gradientNonNonYesYestransport moleculesNo specificity Specificity Specificity Specificity metabolic energy No needNo NeedNeedNeedSolutes moleculesNot changedChangedChangedChanged3. Describe how conditions influenced the effectiveness of antimicrobial agent activity? (10 Cents)Destruction of microorganisms and inhibition of microbial growth are not simple matters because the efficiency of an antimicrobial agent (an agent that kills microorganisms or inhibits their growth) is affected by at least six factors.(1). Population size. Because an equal fraction of a microbial population is killed during each interval, a larger population requires a longer time to die than a smaller one. (2). Population composition. The effectiveness of an agent varies greatly with the nature of the organisms being treated because microorganisms differ markedly in susceptibility. Bacterial endospores are much more resistant to most antimicrobial agents than are vegetative forms, and younger cells are usually more readily destroyed than mature organisms. (3). Concentration or intensity of an antimicrobial agent. Often, but not always, the more concentrated a chemical agent or intense a physical agent, the more rapidly microorganisms are destroyed. However, agent effectiveness usually is not directly related to concentration or intensity. Over a short range a small increase in concentration leads to an exponential rise in effectiveness; beyond a certain point, increases may not raise the killing rate much at all.(4). Duration of exposure. The longer a population is exposed to a microbicidal agent, the more organisms are killed .(5). Temperature. An increase in the temperature at which a chemical acts often enhances its activity. Frequently a lower concentration of disinfectant or sterilizing agent can be used at a higher temperature.(6). Local environment. The population to be controlled is not isolated but surrounded by environmental factors that may either offer protection or aid in its destruction.选择题：（20分）1。分解是一种代谢中_分子转换成_分子。答：大，小角氨基酸，蛋白质B .小，大D食品，仓储2。杀微生物剂有什么影响？A .消毒B抑制微生物C .对人体细胞的毒性D .破坏微生物3。环境因素如温度、酸碱度施加影响的_微生物细胞。C.膜酶B . D NA D细胞壁4。一般来说，真菌中获得的营养物质通过C.光合作用消化有机基板B.吞噬细菌寄生5。两鞭毛和纤毛被发现主要是in_C.海藻真菌B .原生动物D都和丙型肝炎6。以下哪个是没有发现在所有细菌细胞？答：细胞膜C核糖体一类核D胶囊7。菌毛的管状轴_bacteria，作为一种手段，_。A .革兰氏阳性，遗传交流B .革兰氏阳性，附件C .革兰氏阴性菌，遗传交流D .革兰氏阴性，保护8。以下哪个是主要的细菌细胞壁的功能？A .运输支持B . D粘附运动9。细菌安排包八细胞被描述为一个_。答：微角四分B .双球菌d.sarcina10。细菌的遗传分析包括A .发酵试验B .消化能力，复合营养素C存在氧化酶D