微生物期末英文习题答案

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, storage 2. A microbicidal agent has what effect? a. sterilizes b. inhibits microorganisms c. is toxic to human cells d. destroys microorganisms 3. Environmental factors such as temperature and pH exert their effect on the ___ of microbial cells. a. membranes c. enzymes b. DNA d. cell wall 4. In general , fungi derive nutrients through a. photosynthesis c. digesting organic substrates b. engulfing bacteria d. parasitism 5. 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. capsule 7. 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, protection 8. Which of the following is a primary bacteria cell wall function ? a. transport c. support b. motility d. adhesion 9. A bacterial arrangement in packets of eight cells is described as a __ . a. micrococcus c. tetrad b. diplococcus d.sarcina 10. Genetic analysis of bacteria would include a. fermentation testing b. ability to digest complex nutrients c. presence of oxidase d. G+C content 11. In general, if two haploid cells fuse , __will result . a. a germ cell c. mitosis b. a diploid zygote d. meiosis 12. What is embedded in rough endoplasmic reticulum ? a. ribosomes c. chromatin b. Golgi apparatus d. vesicles 13. In general , fungi derive nutrients through a. photosynthesis c. digesting organic substrates b. engulfing bacteria d. parasitism 14. 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. chemoheterotroph 15. An obligate halophile high a. pH c. salt b. temperature d. pressure 16. 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, storage 17. 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 labile 18. Many coenzymes are a. metals c. proteins b. vitamins d. substrates 19. 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 psi 20. 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 organism’s 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 organism’s 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 Koch’s postulates. why are they important?(10 Cents) Koch’s 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 Koch’s 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 surfa