front 1 What is a bacterial colony? | back 1 A visible mass of millions of bacterial cells |
front 2 What does each individual colony represent? | back 2 The progeny of a single cell |
front 3 Which characteristic is NOT used to describe bacterial colonies? | back 3 Genetic material |
front 4 Why is colony morphology important in bacterial identification? | back 4 It is genetically determined and helps differentiate species |
front 5 What is the significance of producing isolated colonies in bacterial identification? | back 5 It ensures the purity of the culture for accurate identification |
front 6 Which of the following is a characteristic used to describe bacterial colonies? | back 6 Odor |
front 7 What does the term 'pure culture' refer to in microbiology? | back 7 A culture containing only one species or strain of bacteria |
front 8 What does the appearance of bacterial colonies depend on? | back 8 The species or strain of bacteria and substances they produce |
front 9 What is the primary function of flagella in bacteria? | back 9 Motility |
front 10 Which flagellar arrangement describes a single flagellum at one pole of the cell? | back 10 Monotrichous |
front 11 What is the main challenge of using transmission electron microscopy to observe flagella? | back 11 It is costly and technically challenging |
front 12
| back 12 Random movement of particles due to collisions with atoms or molecules |
front 13
| back 13 To confirm true motility |
front 14 14. What is the concentration of agar used in a semi-solid motility medium? | back 14 0.5% |
front 15
| back 15 To act as an electron acceptor and indicate bacterial presence |
front 16
| back 16 Red |
front 17 What is the purpose of using a concave slide in a wet-mount preparation? | back 17 To observe motile organisms directly |
front 18
| back 18 Peritrichous |
front 19
| back 19 Pinpoint |
front 20
| back 20 Dissecting scope |
front 21
| back 21 B) Margin |
front 22
| back 22 B) From the side of the plate |
front 23 23. What does it mean if a colony is described as opaque? | back 23 It blocks most of the light |
front 24 24. What indicates that bacteria produce an intracellular pigment? | back 24 The colony becomes colored |
front 25
media? | back 25 B) Nonpigmented |
front 26 26. Why should the plate be placed in an inverted position during incubation? | back 26 D) To prevent condensation from dripping onto the colonies |
front 27 27. What causes microbial colonies to be colored? | back 27 C) Both intracellular and extracellular pigments |
front 28 28. What happens to the media if the organism produces an extracellular pigment? | back 28 B) The media becomes colored |
front 29 29. Which of the following describes the different degrees of opacity in microbial colonies? | back 29 A) Transparent, translucent, opaque |
front 30 30. Why is it preferable to mark the bottom of the Petri dish rather than the top? | back 30 B) To ensure the markings are not erased during incubation |
front 31 31. Why must you flame the loop in between each set of streaks? | back 31 A) To sterilize the loop and prevent cross-contamination |
front 32 32. What is the common method used to isolate organisms in microbiology? | back 32 B) Spread plate method |
front 33 33. Why should you “drag” organisms from the previous streak section for only part of the streaking of the next section? | back 33 B) To create a dilution gradient and isolate individual colonies |
front 34 34. What is the purpose of using a broth culture as inoculum in the
streak plate | back 34 B) To ensure a uniform distribution of bacteria |
front 35 35. What is the recommended incubation temperature for the streak plate method? | back 35 C) 37°C |
front 36 36. Why is it important to use sterile technique when obtaining organisms from broth or solid medium? | back 36 B) To prevent contamination |
front 37 37. What is the ideal characteristic of an antimicrobial drug? | back 37 A) It kills the harmful organism without damaging the host |
front 38
| back 38 B) Due to the development of antibiotic resistance |
front 39 39. What was the purpose of the earliest methods of utilizing agar media in the 1940s? | back 39 B) To determine the minimum inhibitory concentration (MIC) of antimicrobial agents |
front 40 40. What is the Kirby-Bauer method also known as? | back 40 B) Disk diffusion method |
front 41 41. What does a clear zone around a disk in the Kirby-Bauer method indicate? | back 41 B) The absence of bacterial growth |
front 42 42. What factors determine the size of the zone of inhibition in the Kirby-Bauer method? | back 42 B) The relative susceptibility of the microbe and the diffusion rate of the chemical |
front 43 43. What are the possible results reported in the Kirby-Bauer method? | back 43 B) Sensitive, intermediate, or resistant |
front 44 44. Why are antibiotics not effective against viruses? | back 44 B) Antibiotics target bacterial structures and functions, not viral ones |
front 45 45. What type of radiation is ultraviolet radiation classified as? | back 45 B) Non-ionizing radiation |
front 46 46. What type of damage does ultraviolet radiation cause to DNA? | back 46 B) Formation of pyrimidine dimers |
front 47 47. Which nitrogenous bases are typically involved in the formation of pyrimidine dimers due to UV radiation? | back 47 D) Thymine and thymine |
front 48 48. What is the wavelength range of UV-C radiation used in Ultraviolet Growth Inhibition (UVGI)? | back 48 A) 100 to 280 nm |
front 49 49. What is the primary effect of UV-C radiation on bacteria? | back 49 B) It causes mutations or cell death |
front 50 50. Why is UV-C radiation considered to have maximum germicidal effect? | back 50 C) It has the shortest wavelength and highest energy |
front 51 51. What is the main application of Ultraviolet Growth Inhibition (UVGI)? | back 51 B) Sterilizing medical instruments and surfaces |
front 52 52. What is a potential health risk of exposure to UV-C radiation for humans? | back 52 A) Increased risk of skin cancer |
front 53 53. What is one way microorganisms adjust their environment to survive? | back 53 By changing the temperature or pH of the environment |
front 54 54. What is a side effect of bacterial metabolism and infection? | back 54 Disease |
front 55 55. What is the primary difference between Gram-positive and Gram-negative bacteria? | back 55 Gram-positive bacteria have a thick layer of peptidoglycan within their cell wall |
front 56 56. What is the Enterotube II system specifically used for? | back 56 Identifying bacterial enzymes and fermentations |
front 57 57. How do commercial rapid diagnostic kits, like the Enterotube II system, benefit laboratory technicians? | back 57 They save money, effort, and critical diagnostic time |
front 58 58. Which growth pattern is characterized by bacteria floating on the top of the broth due to a waxy cell wall or gas vacuole? | back 58 . Pellicle |
front 59 59. What can cause changes in the expected growth patterns of bacteria in broth? | back 59 Differences in incubation conditions such as time, temperature, pH, and nutrient composition |
front 60 60. What is the term for the growth pattern where bacteria form clumps or aggregates throughout the broth? | back 60 . Flocculent |
front 61 61. Which factor is NOT mentioned as potentially altering bacterial growth patterns in broth? | back 61 The type of Petri dish used |
front 62 62. What is the significance of colony morphology in identifying unknown bacteria? | back 62 It helps differentiate between bacteria based on their growth patterns |
front 63 63. What are the two purposes of the enzyme urease in bacteria? | back 63 Neutralizing acidic environments and providing nitrogen for protein synthesis |
front 64 64. Which of the following is NOT a component of Rustigian and Stuart’s Urea broth? | back 64 . Dextrose |
front 65 65. What color change indicates a urease-positive organism in the urea broth? | back 65 Pink to orange |
front 66 66. What is the purpose of the Durham tube in the phenol red experiment? | back 66 To collect gases formed as by-products of sugar fermentation |
front 67 67. What color change indicates acid production in the phenol red experiment? | back 67 Red to yellow or orange |
front 68 68. What is the primary purpose of Fluid Thioglycollate (FTG) medium? | back 68 To determine whether a bacterium is an aerobe or an anaerobe |
front 69 69. What role does resazurin play in the FTG medium? | back 69 It acts as an indicator of oxidation-reduction |
front 70 70. Where in the FTG medium would you expect to find obligate anaerobes growing? | back 70 At the bottom of the tube |
front 71 71. What is the function of catalase in bacteria? | back 71 To neutralize hydrogen peroxide by degrading it into water and oxygen |
front 72 72. Which of the following bacteria are catalase positive? | back 72 Staphylococcal spp |
front 73 73. What indicates a positive catalase test result? | back 73 Formation of bubbles |
front 74 74. What is the role of cytochrome c oxidase in the electron transport chain (ETC)? | back 74 To donate electrons to oxygen to form water |
front 75 75. Which reagent is used in the oxidase test to identify cytochrome c oxidase–positive organisms? | back 75 Tetramethyl-p-phenylene diamine |
front 76 76. What color change indicates a positive result in the oxidase test? | back 76 Dark blue/purple |
front 77 77. What enzyme do Proteus and Providencia species produce that removes the amine group from phenylalanine? | back 77 . Phenylalanine deaminase |
front 78 78. What color change indicates a positive result for phenylalanine deaminase activity? | back 78 . Yellow to green |
front 79 79. What is the purpose of the 12% ferric chloride (FeCl3) reagent in the phenylalanine deaminase test? | back 79 To react with keto-acids like phenylpyruvic acid to produce a green color |
front 80 80. What is the role of lipase in bacteria? | back 80 To hydrolyze lipids into smaller subunits |
front 81 81. What indicates lipolytic activity in a lipase-positive organism on tributyrin agar? | back 81 . A clearing or dark halo around the bacterial growth |
front 82 82. Which of the following is NOT a component of the media used for testing lipolytic activity? | back 82 . Glucose |
front 83 83. What does SIM stand for in the context of microbiological testing? | back 83 . Sulfur, indole, and motility |
front 84 84. What is the purpose of sodium thiosulfate in SIM media? | back 84 To act as a sulfur source |
front 85 85. Why is SIM medium considered a combination differential media? | back 85 It tests for multiple biochemical features specific to Enterobacteriaceae family members |
front 86 86. What is the purpose of the MR-VP broth in glucose fermentation testing? | back 86 To test for the pathway used to ferment glucose |
front 87 87. Which fermentation pathway is detected by the Voges-Proskauer test? | back 87 . Butanediol fermentation |
front 88 88. What is the pH range at which methyl red changes color to indicate a positive result for mixed acid fermentation? | back 88 Below 4.5 |
front 89 89. Which of the following is NOT a product of the mixed acid fermentation pathway? | back 89 . 2,3-butanediol |
front 90 90. What does the Voges-Proskauer test detect in glucose fermentation? | back 90 The production of acetoin and 2,3-butanediol |
front 91 91. What is the sole carbon source in Simmon’s citrate medium? | back 91 . Sodium citrate |
front 92 92. What color change indicates a positive result for citrate utilization in Simmon’s citrate medium? | back 92 Green to blue |
front 93 93. What compound is formed in the medium as a result of citrate hydrolysis and subsequent reactions? | back 93 . Sodium carbonate |
front 94 94. What is the purpose of cooling the gelatin medium to below 25°C after incubation? | back 94 To solidify the gelatin if it is still present |
front 95 95. What indicates a positive result for gelatinase activity in the gelatin medium? | back 95 The medium remains liquid after cooling |
front 96 96. What does the enzyme gelatinase hydrolyze gelatin into? | back 96 . Peptides and amino acids |
front 97 97. What are the two glucose polymers that make up a molecule of starch | back 97 Amylose and amylopectin |
front 98 98. What indicates a positive starch test when iodine is added to the medium? | back 98 A colorless (golden) halo around the bacterial growth |
front 99 99. What is the role of the enzyme amylase in bacteria? | back 99 To hydrolyze starch into smaller molecules like dextrins, maltose, and glucose |
front 100 100. How do nonmotile bacteria grow in the motility test medium? | back 100 They grow along the stab line |
front 101 101. What color change occurs in the motility test medium when triphenyltetrazolium chloride (TTC) is reduced by bacterial metabolism? | back 101 Colorless to red |
front 102 102. What is the primary by-product of sucrose fermentation by Streptococcus species in the oral cavity? | back 102 Dextran |
front 103 103. What role does dextran play in the formation of dental caries? | back 103 . It forms a biofilm that helps retain organic acids on the tooth surface |
front 104 104. Why is effective brushing and flossing important in preventing dental caries? | back 104 It removes plaque, which contains the biofilm and bacteria |
front 105 105. What factors determine the specificity of normal microbial flora in different locations within the body? | back 105 Oxygen concentration, pH, moisture, and types of secretions |
front 106 106. What indicates alpha hemolysis on blood agar plates (BAPs)? | back 106 A greening of the plate around the colony |
front 107 107. Which type of agar plate is used for the isolation and differentiation of Staphylococci? | back 107 Mannitol salt agar plates |
front 108 108. How are the four major classes of the phylum Protozoa distinguished? | back 108 By their locomotor or reproductive structures |
front 109 109. What are the two primary forms of amoeba found in their host? | back 109 Trophozoites and cysts |
front 110
| back 110 . In fresh diarrheal stools |
front 111 111. Which characteristic is diagnostic for the trophozoite of E. histolytica? | back 111 Ingested red blood cells (RBCs) |
front 112 112. How is the cyst of E. coli distinguished from that of E. histolytica? | back 112 . Presence of eight nuclei with short chromatoid bodies |
front 113 113. Which organism does not form cysts and has a trophozoite with one or two nuclei arranged at opposite ends of the cell? | back 113 . D. fragilis |
front 114 114. Which characteristic is unique to the trophozoite of C. mesnili? | back 114 . Bilaterally symmetrical with two sucking disks |
front 115 115. How can the cyst of G. lamblia be described? | back 115 Lemon-shaped with a protrusion at the anterior end |
front 116 116. Which organism is found only as a feeding trophozoite and has no cyst stage? | back 116 . T. hominis |
front 117 117. What are the two large groups of helminths? | back 117 . Trematodes and nematodes |
front 118 118. How are tapeworms (cestodes) different from flukes (trematodes)? | back 118 Tapeworms are segmented, while flukes are not segmented |
front 119 119. What is a proglottid in the context of tapeworms? | back 119 . A segment containing male and female sexual organs |
front 120 120. What are the three different organisms in the Fungus group mentioned in the text? | back 120 Mushrooms, molds, and yeasts |
front 121 121. How are molds in the Fungi Imperfecti group identified? | back 121 By their method of spore formation |
front 122 122. Which fungal group includes the common yeast used in bread baking and beer production? | back 122 Ascomycetes |
front 123 123. What is the primary difference between fungal and plant cell walls? | back 123 Fungal cell walls are composed of chitin, while plant cell walls are composed of cellulose. |
front 124 124. Which type of fungal spore is formed within a sac called a sporangium? | back 124 Sporangiospores |
front 125 125. What role do vegetative hyphae play in molds? | back 125 They anchor the fungus and absorb nutrients |
front 126 126. What is the primary function of hyphae in mycelial fungi? | back 126 To absorb food after decomposing it with enzymes |
front 127 127. Which phylum of fungi is responsible for producing most mushrooms? | back 127 Basidiomycota |
front 128 128. What is a notable feature of fungi compared to most bacteria? | back 128 . Fungi can reproduce both asexually and sexually |
front 129 129. Why is the Zygomycota group no longer considered an official phylum by fungal taxonomists? | back 129 They are not an evolutionarily unified group |
front 130 130. What type of symbiotic relationship do lichens represent? | back 130 Mutualistic |
front 131 131. What is a key feature of ectomycorrhizal fungi? | back 131 They are found on the roots of conifers and other woody plants |
front 132 132. What is a key difference between yeast fungi and mycelial fungi? | back 132 . Yeast fungi are unicellular, while mycelial fungi are multicellular. |
front 133 133. Which mechanism is the most common for asexual reproduction in yeasts? | back 133 Budding |
front 134 134. What role does S. cerevisiae play in human activities? | back 134 It is used in baking and alcoholic beverage production |
front 135 135. What is the dormant, nonmotile stage in the life cycle of Protozoa called? | back 135 . Cyst |
front 136 136. Which group of organisms includes mosquitoes, ticks, lice, bed bugs, and fleas? | back 136 Arthropods |
front 137 137. What is the primary characteristic of algae that differentiates them from Protozoa? | back 137 Algae contain cellulose and pectin in their cell walls |
front 138 138. What is the primary function of the pellicule in protozoa? | back 138 To protect the cell and assist in food ingestion |
front 139 139. How are medically important Helminthes classified? | back 139 By their phyla: Platyhelminthes and Nematoda |
front 140 140. What is a characteristic feature of flatworms in the phylum Platyhelminthes? | back 140 They absorb food directly across a nonliving covering called a cuticle |
front 141 141. How do members of the Mastigophora move? | back 141 By using flagella |
front 142 142. What is a characteristic feature of organisms classified as Ciliophora? | back 142 . They use cilia for movement and feeding. |
front 143 143. Which organism is the agent of toxoplasmosis? | back 143 . Toxoplasma gondii |
front 144 144. What is the primary characteristic of the Apicomplexa (Sporozoa)? | back 144 They have a complex life cycle and are all parasites |
front 145 145. Which organism is observed in a blood smear from a patient with malaria? | back 145 . Plasmodium falciparum |
front 146 146. What is the shape of the nucleus in Stentor? | back 146 Resembling a string of beads |
front 147 147. What type of motility do members of Sarcodina (amoeba and related organisms) use? | back 147 Pseudopodia |
front 148 148. Which organism is associated with the sexually transmitted disease trichomoniasis? | back 148 . Trichomonas vaginalis |
front 149 149. What is the function of the contractile vacuoles in Paramecium? | back 149 Regulation of osmotic balance |
front 150 150. Who discovered the ABO blood group system? | back 150 Karl Landsteiner |
front 151 151. What antigens are present on the red blood cells of a person with type AB blood? | back 151 Both A and B antigens |
front 152 152. Which blood type has antibodies against both A and B antigens in
their plasma? | back 152 Type O |
front 153 153. What happens during a Type II cytotoxic reaction in an incompatible blood transfusion? | back 153 The recipient’s antibodies react with the donor’s RBC antigens |
front 154 154. What is the Rh factor? | back 154 An antigen found on RBCs |
front 155 155. What can happen if an Rh− mother becomes sensitized to Rh+ blood and conceives a second Rh+ child? | back 155 The mother’s antibodies may attack the child’s RBCs |
front 156 156. What is hemolytic disease of the newborn (HDNB)? | back 156 A condition where the mother’s antibodies attack the child’s RBCs |
front 157 157. Why are individuals with type O blood called “universal donors”? | back 157 They have neither A nor B antigens |
front 158 158. Why are individuals with type AB blood called “universal recipients”? | back 158 They can receive blood from any donor without adverse reactions |
front 159 159. What triggers the production of antibodies against Rh factor in an Rh− person? | back 159 Exposure to Rh+ blood |