BIO 2923 TEST 3 (Bacteria, Growth medium, d., E.)/ with answer key/ 100% CORRECT SOLUTIONS

BIO 2923 TEST 3 BIO 2923 TEST 3 Student: 1. The Five I's of studying microorganisms include all of the following except: A. inoculation B. incubation C. infection D. isolation E. identific ation 2. All of the following are examples of different types of microbiological media except: A. broth B. enriched C. agar D. petri dish E. gel 3. The term that refers to the purposeful addition of microorganisms into a laboratory nutrient medium is: A. isolation B. inoculation C. immunization D. infection E. contamination 4. Which of the following is essential for development of discrete, isolated colonies? A. broth medium B. differential medium C. selective medium D. solid medium E. assay medium 5. A pure culture contains only: A. one species of microorganism B. bacteria C. a variety of microbes from one source D. a variety of species from the same genus E. none of the choices are correct 6. Which of the following will result when 1% to 5% agar is added to nutrient broth, boiled and cooled? A. a pure culture B. a mixed culture C. a solid medium D. a liquid medium E. a contaminated medium 7. Agar is an important component of media because A. bacteria require agar to grow B. agar inhibits mold growth C. agar provides a solid surface for bacterial growth D. agar prevents contamination E. all of the choices are correct 8. A microbiologist inoculates Staphylococcus aureus into a culture medium. Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis are determined to be growing in this culture. What is the most likely explanation? A. the microbiologist used too much inoculum B. the culture is contaminated C. the incubation temperature was incorrect D. the culture medium must be selective E. the culture medium must be differential 9. Bacteroides is inoculated into a pour plate. After incubation, colonies are only seen within the agar and not on the surface. Bacteroides must be: A. aerobic B. axenic C. anaerobic D. in selective media E. in differential media 10. A microbiologist inoculates Staphylococcus epidermidis and Escherichia coli into a culture medium. Following incubation, only the E. coli grows in the culture. What is the most likely explanation? A. the microbiologist used too much inoculum B. the culture is contaminated C. the incubation temperature was incorrect D. the culture medium must be selective E. the culture medium must be differential 11. Which method often results in colonies developing down throughout the agar and some colonies on the surface: A. streak plate B. spread plate C. pour plate D. all of the choices are correct E. none of the choices are correct 12. A common medium used for growing fastidious bacteria is: A. blood agar B. trypticase soy agar C. mannitol salt agar D. MacConkey medium E. a reducing medium 13. A nutrient medium that has all of its chemical components identified and their precise concentrations known and reproducible, would be termed: A. complex B. reducing C. enriched D. synthetic E. none of the choices are correct 14. A reducing medium contains: A. sugars that can be fermented B. extra oxygen C. hemoglobin, vitamins or other growth factors D. substances that remove oxygen E. inhibiting agents 15. Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium? A. differential B. selective C. enumeration D. enriched E. reducing 16. A microbiologist decides to use a nutrient medium that contains thioglycollic acid. What type of microbe is she attempting to culture? A. fastidious B. gram positive C. anaerobe D. gram negative E. aerobic 17. Differential media results in which of the following growth characteristics? A. different color colonies B. different media color post incubation C. precipitates D. gas bubbles E. all of the choices are correct 18. A reducing media is used to culture A. fastidious organisms B. aerobic organisms C. anaerobic organisms D. any pathogenic organisms E. none of the choices are correct 19. For which bacterial genus is mannitol salt agar selective? A. Salmonella B. Streptococcus C. Neisseria D. Staphylococcus E. Escherichia 20. A microbiologist must culture a patient's feces for intestinal pathogens. Which of the following would likely be present in selective media for analyzing this fecal specimen? A. NaCl B. sheep red blood cells C. bile salts D. thioglycollic acid E. peptone 21. Which of the following characteristics refers to the microscope's ability to show two separate entities as separate and distinct? A. resolving power B. magnification C. refraction D. all of the choices are correct E. none of the choices are correct 22. Which of the following magnifies the specimen to produce the real image of the specimen? A. condenser B. objective lens C. ocular lens D. body E. nosepiece 23. Which of the following magnifies the specimen to produce the virtual image of the specimen? A. objective lens B. ocular lens C. condenser D. body E. iris 24. If a microbiologist is studying a specimen at a total magnification of 950X, what is the magnifying power of the objective lens if the ocular lens is 10X? A. 100X B. 950X C. 85X D. 850X E. 95X 25. All of the following are diameters of cells that would be resolved in a microscope with a limit of resolution of 0.2µm except: A. 0.2 µm B. 0.2 mm C. 0.1 µm D. 0.3 µm E. 2.0 µm 26. The wavelength of light used plus the numerical aperature governs: A. illumination B. resolution C. magnification D. size of the field E. all of the choices are correct 27. The type of microscope in which you would see brightly illuminated specimens against a black background is: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron 28. This microscope does not use light in forming the specimen image: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron 29. This microscope achieves the greatest resolution and highest magnification: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron 30. This microscope shows cells against a bright background and also shows intracellular structures of unstained cells based on their varying densities: A. bright-field B. dark-field C. phase-contrast D. differential interference E. electron 31. This microscope cannot image live specimens. A. bright-field B. phase-contrast C. dark-field D. scanning electron E. differential interference 32. This microscope is the most widely used and shows cells against a bright background: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron 33. All of the following pertain to the fluorescence microscope except: A. uses electron's to produce a specimen image B. type of compound microscope C. requires the use of dyes like acridine and fluorescein D. commonly used to diagnose certain infections E. requires an ultraviolet radiation source 34. A confocal scanning optical microscope: A. uses ultraviolet light to form a specimen image B. shows three-dimensional cell images from the cell surface to the middle of the cell C. produces specimen images on electron micrographs D. uses dyes that emit visible light when bombarded by ultraviolet rays E. requires specimens to be stained 35. Which microscope bombards a whole, metal-coated specimen with electrons moving back and forth over it: A. fluorescence B. differential interference contrast C. scanning electron D. transmission electron E. phase-contrast 36. The specimen preparation that is best for viewing cell motility is: A. hanging drop B. fixed stained smear C. gram stain D. negative stain E. flagellar stain 37. The purpose of staining cells on a microscope slide is to: A. kill them B. secure them to the slide C. enlarge the cells D. add contrast in order to see them better E. see motility 38. The Gram stain, acid-fast stain and endospore stain have the following in common: A. used on a wet mount of the specimen B. use heat to force the dye into cell structures C. outcome based on cell wall differences D. use a negative stain technique E. are differential stains 39. Basic dyes are: A. attracted to the acidic substances of bacterial cells B. anionic C. used in negative staining D. repelled by cells E. dyes such as India ink and nigrosin 40. A microbiologist makes a fixed smear of bacterial cells and stains them with Loeffler's methylene blue. All the cells appear blue under the oil lens. This is an example of: A. negative staining B. using an acidic dye C. simple staining D. using the acid-fast stain E. capsule staining 41. The correct microbiological term for the tiny sample of specimen that is put into a nutrient medium in order to produce a culture is the . A. colony B. inoculum C. streak D. loop E. none of the choices are correct 42. The three physical forms of laboratory media are: A. solid, liquid, gas B. solid, semisolid, liquid C. streak plate, pour plate, broth D. aerobic, anaerobic, microaerobic E. none of the choices are correct 43. Bacteria that require special growth factors and complex nutrients are termed . A. aerobic B. anaerobic C. fastidious D. microaerophilic E. autotrophic 44. is the term for a culture made from one isolated colony. A. axenic B. mixed C. pure D. both axenic and mixed E. both axenic and pure 45. Newly inoculated cultures must be at a specific temperature and time to encourage growth. A. streaked B. poured C. incubated D. all of the choices are correct 46. Magnification is achieved in a compound microscope through the initial magnification of the specimen by the lens. This image is then projected to the lens that will further magnify the specimen to form a virtual image received by the eye. A. ocular, objective B. scanning, objective C. objective, ocular D. ocular, oil E. none of the choices are correct 47. The of the microscope holds and allows selection of the objective lenses. A. stage B. condenser C. objective D. ocular E. condenser 48. dyes have positive charges on the chromophore and are repelled by bacterial cells. A. Basic B. Acidic C. Acid fast D. Simple E. Differential 49. has the same optical qualities as glass and thus prevents refractive loss of light as it passes from the slide to the objective lens. A. The scanning objective B. The oil objective C. The slide D. Immersion oil E. The ocular 50. The procedures for culturing a microorganism requires the use of a microscope. True False 51. One colony typically develops from the growth of several parent bacterial cells. True False 52. Some microbes are not capable of growing on artificial media. True False 53. Mixed cultures are also referred to as contaminated cultures. True False 54. A medium that is gel-like has less agar in it compared to a solid medium. True False 55. A selective medium contains one or more substances that inhibit growth of certain microbes in order to facilitate the growth of other microbes. True False 56. A bacterial species that grows on blood agar but will not grow on trypticase soy agar is termed an anaerobe. True False 57. Fixed smears of specimens are required in order to perform the Gram stain and endospore stain on the specimens. True False 58. The bending of light rays as they pass form one medium to another is called refraction. True False 59. At the end of the Gram stain, gram positive bacteria will be seen as pink cells. True False 60. Scanning tunneling microscopes can give close-up views of DNA molecules, while the scanning probe microscopes have the potential to see individual atoms. True False 61. Compare and contrast the reagents and functions of negative staining versus positive staining. 62. Explain the difference and significance between a contaminated culture and a mixed culture. 63. A contaminated food sample contains several different species of bacteria. A food microbiologist is interested in studying just one of these species. Describe the sequence of procedures that the microbiologist must perform in order to obtain a pure culture of the bacterial species of interest from this food sample. Detail all the necessary media and equipment. 64. Explain how and why immersion oil increases resolution but not magnification when using the 100X objective. 3 Key 1. The Five I's of studying microorganisms include all of the following except: A. inoculation B. incubation C. infection D. isolation E. identification Cowan - 003 Chapter... #1 2. All of the following are examples of different types of microbiological media except: A. broth B. enriched C. agar D. petri dish E. gel Cowan - 003 Chapter... #2 3. The term that refers to the purposeful addition of microorganisms into a laboratory nutrient medium is: A. isolation B. inoculation C. immunization D. infection E. contamination 4. Which of the following is essential for development of discrete, isolated colonies? A. broth medium B. differential medium C. selective medium D. solid medium E. assay medium Cowan - 003 Chapter... #3 5. A pure culture contains only: A. one species of microorganism B. bacteria C. a variety of microbes from one source D. a variety of species from the same genus E. none of the choices are correct Cowan - 003 Chapter... #4 Cowan - 003 Chapter... #5 6. Which of the following will result when 1% to 5% agar is added to nutrient broth, boiled and cooled? A. a pure culture B. a mixed culture C. a solid medium D. a liquid medium E. a contaminated medium Cowan - 003 Chapter... #6 7. Agar is an important component of media because A. bacteria require agar to grow B. agar inhibits mold growth C. agar provides a solid surface for bacterial growth D. agar prevents contamination E. all of the choices are correct Cowan - 003 Chapter... #7 8. A microbiologist inoculates Staphylococcus aureus into a culture medium. Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis are determined to be growing in this culture. What is the most likely explanation? A. the microbiologist used too much inoculum B. the culture is contaminated C. the incubation temperature was incorrect D. the culture medium must be selective E. the culture medium must be differential Cowan - 003 Chapter... #8 9. Bacteroides is inoculated into a pour plate. After incubation, colonies are only seen within the agar and not on the surface. Bacteroides must be: A. aerobic B. axenic C. anaerobic D. in selective media E. in differential media Cowan - 003 Chapter... #9 10. A microbiologist inoculates Staphylococcus epidermidis and Escherichia coli into a culture medium. Following incubation, only the E. coli grows in the culture. What is the most likely explanation? A. the microbiologist used too much inoculum B. the culture is contaminated C. the incubation temperature was incorrect D. the culture medium must be selective E. the culture medium must be differential Cowan - 003 Chapter... #10 11. Which method often results in colonies developing down throughout the agar and some colonies on the surface: A. streak plate B. spread plate C. pour plate D. all of the choices are correct E. none of the choices are correct Cowan - 003 Chapter... #11 12. A common medium used for growing fastidious bacteria is: A. blood agar B. trypticase soy agar C. mannitol salt agar D. MacConkey medium E. a reducing medium Cowan - 003 Chapter... #12 13. A nutrient medium that has all of its chemical components identified and their precise concentrations known and reproducible, would be termed: A. complex B. reducing C. enriched D. synthetic E. none of the choices are correct Cowan - 003 Chapter... #13 14. A reducing medium contains: A. sugars that can be fermented B. extra oxygen C. hemoglobin, vitamins or other growth factors D. substances that remove oxygen E. inhibiting agents Cowan - 003 Chapter... #14 15. Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium? A. differential B. selective C. enumeration D. enriched E. reducing Cowan - 003 Chapter... #15 16. A microbiologist decides to use a nutrient medium that contains thioglycollic acid. What type of microbe is she attempting to culture? A. fastidious B. gram positive C. anaerobe D. gram negative E. aerobic 17. Differential media results in which of the following growth characteristics? A. different color colonies B. different media color post incubation C. precipitates D. gas bubbles E. all of the choices are correct Cowan - 003 Chapter... #16 18. A reducing media is used to culture A. fastidious organisms B. aerobic organisms C. anaerobic organisms D. any pathogenic organisms E. none of the choices are correct Cowan - 003 Chapter... #17 19. For which bacterial genus is mannitol salt agar selective? A. Salmonella B. Streptococcus C. Neisseria D. Staphylococcus E. Escherichia Cowan - 003 Chapter... #18 Cowan - 003 Chapter... #19 20. A microbiologist must culture a patient's feces for intestinal pathogens. Which of the following would likely be present in selective media for analyzing this fecal specimen? A. NaCl B. sheep red blood cells C. bile salts D. thioglycollic acid E. peptone Cowan - 003 Chapter... #20 21. Which of the following characteristics refers to the microscope's ability to show two separate entities as separate and distinct? A. resolving power B. magnification C. refraction D. all of the choices are correct E. none of the choices are correct Cowan - 003 Chapter... #21 22. Which of the following magnifies the specimen to produce the real image of the specimen? A. condenser B. objective lens C. ocular lens D. body E. nosepiece Cowan - 003 Chapter... #22 23. Which of the following magnifies the specimen to produce the virtual image of the specimen? A. objective lens B. ocular lens C. condenser D. body E. iris Cowan - 003 Chapter... #23 24. If a microbiologist is studying a specimen at a total magnification of 950X, what is the magnifying power of the objective lens if the ocular lens is 10X? A. 100X B. 950X C. 85X D. 850X E. 95X Cowan - 003 Chapter... #24 25. All of the following are diameters of cells that would be resolved in a microscope with a limit of resolution of 0.2µm except: A. 0.2 µm B. 0.2 mm C. 0.1 µm D. 0.3 µm E. 2.0 µm Cowan - 003 Chapter... #25 26. The wavelength of light used plus the numerical aperature governs: A. illumination B. resolution C. magnification D. size of the field E. all of the choices are correct Cowan - 003 Chapter... #26 27. The type of microscope in which you would see brightly illuminated specimens against a black background is: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron Cowan - 003 Chapter... #27 28. This microscope does not use light in forming the specimen image: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron Cowan - 003 Chapter... #28 29. This microscope achieves the greatest resolution and highest magnification: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron Cowan - 003 Chapter... #29 30. This microscope shows cells against a bright background and also shows intracellular structures of unstained cells based on their varying densities: A. bright-field B. dark-field C. phase-contrast D. differential interference E. electron Cowan - 003 Chapter... #30 31. This microscope cannot image live specimens. A. bright-field B. phase-contrast C. dark-field D. scanning electron E. differential interference Cowan - 003 Chapter... #31 32. This microscope is the most widely used and shows cells against a bright background: A. bright-field B. dark-field C. phase-contrast D. fluorescence E. electron 33. All of the following pertain to the fluorescence microscope except: A. uses electron's to produce a specimen image B. type of compound microscope C. requires the use of dyes like acridine and fluorescein D. commonly used to diagnose certain infections E. requires an ultraviolet radiation source Cowan - 003 Chapter... #32 34. A confocal scanning optical microscope: A. uses ultraviolet light to form a specimen image Cowan - 003 Chapter... #33 B. shows three-dimensional cell images from the cell surface to the middle of the cell C. produces specimen images on electron micrographs D. uses dyes that emit visible light when bombarded by ultraviolet rays E. requires specimens to be stained Cowan - 003 Chapter... #34 35. Which microscope bombards a whole, metal-coated specimen with electrons moving back and forth over it: A. fluorescence B. differential interference contrast C. scanning electron D. transmission electron E. phase-contrast 36. The specimen preparation that is best for viewing cell motility is: A. hanging drop B. fixed stained smear C. gram stain D. negative stain E. flagellar stain Cowan - 003 Chapter... #35 37. The purpose of staining cells on a microscope slide is to: A. kill them B. secure them to the slide C. enlarge the cells D. add contrast in order to see them better E. see motility Cowan - 003 Chapter... #36 Cowan - 003 Chapter... #37 38. The Gram stain, acid-fast stain and endospore stain have the following in common: A. used on a wet mount of the specimen B. use heat to force the dye into cell structures C. outcome based on cell wall differences D. use a negative stain technique E. are differential stains Cowan - 003 Chapter... #38 39. Basic dyes are: A. attracted to the acidic substances of bacterial cells B. anionic C. used in negative staining D. repelled by cells E. dyes such as India ink and nigrosin Cowan - 003 Chapter... #39 40. A microbiologist makes a fixed smear of bacterial cells and stains them with Loeffler's methylene blue. All the cells appear blue under the oil lens. This is an example of: A. negative staining B. using an acidic dye C. simple staining D. using the acid-fast stain E. capsule staining Cowan - 003 Chapter... #40 41. The correct microbiological term for the tiny sample of specimen that is put into a nutrient medium in order to produce a culture is the . A. colony B. inoculum C. streak D. loop E. none of the choices are correct Cowan - 003 Chapter... #41 42. The three physical forms of laboratory media are: A. solid, liquid, gas B. solid, semisolid, liquid C. streak plate, pour plate, broth D. aerobic, anaerobic, microaerobic E. none of the choices are correct Cowan - 003 Chapter... #42 43. Bacteria that require special growth factors and complex nutrients are termed . A. aerobic B. anaerobic C. fastidious D. microaerophilic E. autotrophic Cowan - 003 Chapter... #43 44. is the term for a culture made from one isolated colony. A. axenic B. mixed C. pure D. both axenic and mixed E. both axenic and pure Cowan - 003 Chapter... #44 45. Newly inoculated cultures must be at a specific temperature and time to encourage growth. A. streaked B. poured C. incubated D. all of the choices are correct Cowan - 003 Chapter... #45 46. Magnification is achieved in a compound microscope through the initial magnification of the specimen by the lens. This image is then projected to the lens that will further magnify the specimen to form a virtual image received by the eye. A. ocular, objective B. scanning, objective C. objective, ocular D. ocular, oil E. none of the choices are correct Cowan - 003 Chapter... #46 47. The of the microscope holds and allows selection of the objective lenses. A. stage B. condenser C. objective D. ocular E. condenser Cowan - 003 Chapter... #47 48. dyes have positive charges on the chromophore and are repelled by bacterial cells. A. Basic B. Acidic C. Acid fast D. Simple E. Differential Cowan - 003 Chapter... #48 49. has the same optical qualities as glass and thus prevents refractive loss of light as it passes from the slide to the objective lens. A. The scanning objective B. The oil objective C. The slide D. Immersion oil E. The ocular 50. The procedures for culturing a microorganism requires the use of a microscope. FALSE Cowan - 003 Chapter... #49 51. One colony typically develops from the growth of several parent bacterial cells. FALSE Cowan - 003 Chapter... #50 52. Some microbes are not capable of growing on artificial media. TRUE Cowan - 003 Chapter... #51 53. Mixed cultures are also referred to as contaminated cultures. FALSE Cowan - 003 Chapter... #52 54. A medium that is gel-like has less agar in it compared to a solid medium. TRUE Cowan - 003 Chapter... #53 Cowan - 003 Chapter... #54 55. A selective medium contains one or more substances that inhibit growth of certain microbes in order to facilitate the growth of other microbes. TRUE Cowan - 003 Chapter... #55 56. A bacterial species that grows on blood agar but will not grow on trypticase soy agar is termed an anaerobe. FALSE Cowan - 003 Chapter... #56 57. Fixed smears of specimens are required in order to perform the Gram stain and endospore stain on the specimens. TRUE Cowan - 003 Chapter... #57 58. The bending of light rays as they pass form one medium to another is called refraction. TRUE Cowan - 003 Chapter... #58 59. At the end of the Gram stain, gram positive bacteria will be seen as pink cells. FALSE Cowan - 003 Chapter... #59 60. Scanning tunneling microscopes can give close-up views of DNA molecules, while the scanning probe microscopes have the potential to see individual atoms. FALSE Cowan - 003 Chapter... #60 61. Compare and contrast the reagents and functions of negative staining versus positive staining. Answers will vary. Cowan - 003 Chapter... #61 62. Explain the difference and significance between a contaminated culture and a mixed culture. Answers will vary. Cowan - 003 Chapter... #62 63. A contaminated food sample contains several different species of bacteria. A food microbiologist is interested in studying just one of these species. Describe the sequence of procedures that the microbiologist must perform in order to obtain a pure culture of the bacterial species of interest from this food sample. Detail all the necessary media and equipment. Answers will vary. Cowan - 003 Chapter... #63 64. Explain how and why immersion oil increases resolution but not magnification when using the 100X objective. Answers will vary. Cowan - 003 Chapter... #64 3 Summary Category # of Question s Cowan - 003 Chapter... 64 Show Less