Micro Flashcards Unit 1

1) Pieces of deoxyribonucleic acid (DNA) transposons that move from one genetic element to another and contain genes for movement and genes for other features are called 2) Miniature chromosomes composed of plasmids several genes in double-stranded, closed, circular structures are called 3) A DNA sequence that encodes for a gene specific product (ribonucleic acid [RNA] or protein) is defined as a 4) The enzyme that adds nucleotide DNA polymerase bases to each growing daughter strand in the replication process is called 5) If a bacterial cell encounters sporulation unfavorable environmental conditions, then its metabolism will begin to slow until it eventually transforms into an inactive, dormant state. This survival mechanism is known as: 6) Teichoic acids, mycolic acids, Cell wall peptidoglycan, and disaccharide- pentapeptide subunits are all building blocks of which bacterial structure? 7) The major difference between gram- gram-negative bacteria contain an outer positive and gram-negative bacteria is membrane that functions as the cell’s initial that barrier to the environment 8) In gene regulation and mechanism of genetic control in which control, repression is defined as the: genes are not transcribed and therefore are not expressed in the presence of those target products in sufficient supply 9) In gene regulation and mechanism of genetic control in which control, induction can be defined as the: genes are induced only when the substrate to be degraded by enzymatic action is present 10) Mutation is defined as the: internal change in the original nucleotide sequence of a gene or genes within an organism’s genome 11) Recombination is defined as the: change of the bacterial genotypes through the exchange of DNA from one cell to another 12) Transformation is defined as the: uptake of free DNA from the environment and recombination with the recipient’s homologous DNA 13) Transduction is defined as the: mechanism that is mediated by viruses, by which DNA from two bacteria may come together in one cell, thus allowing

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for recombination 14) The mechanism for adenosine substrate-level phosphorylation triphosphate (ATP) production in which high-energy phosphate bonds produced by the central metabolic pathways are donated to adenosine diphosphate (ADP) to form ATP is: 15) A pathway that generates ATP by fermentative metabolism substrate-level phosphorylation that does not require oxygen and produces various end products, including alcohols, acids, carbon dioxide, and hydrogen, is: 16) The pathway of metabolism that oxidative phosphorylation involves a series of electron transfers from reduced carrier molecules such as NADH2 and NADPH2 to a terminal electron acceptor is 17) The term used when oxidative aerobic respiration phosphorylation uses oxygen as the terminal electron acceptor is: 18) Which organelle is found in eukaryotic Lysosomes cells and is responsible for controlled enzymatic degradation of intracellular substances 19) Teichoic acids are glycerol- or ribitol-phosphate polymers that are combined with various sugars, amino acids, and amino sugars, which are a part of the cell wall of gram-positive bacteria. 20) Pieces of DNA that move from transposable elements plasmid to chromosome or vice versa but are not found as separate entities are called: 21) All genes within an organism make up genome that organism’s 22) A bacterial cell that contains teichoic Purple acid stains which color on the Gram stain? 23) A bacterial cell that contains an outer No discrepancy is present; organisms membrane and periplasmic space stains that contain an outer membrane and pink to red on Gram stain. Which one of periplasmic space should stain pink the following statements explains this because of their cell wall composition. discrepancy 24) Amino acids, fatty acids, sugars, and Biosynthesis nucleotides are produced during which metabolic reaction?

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25) A human infection that results from a microorganism that primarily infects Zoonotic animal populations is referred to as a(n) ______infection. 26) Which of the following processes Elongation takes place in the cytoplasm and involves the tRNA mediating the sequential addition of amino acids in a specific sequence that is dictated by the codon sequence of the messenger RNA (mRNA) molecule? 27) The persistent survival of microorganisms on a surface of the Colonization human body is called a(n): 28) Cells that ingest and destroy bacteria Phagocytes and other foreign particles are called: 29) Cells with a short life span that circulate in blood and tissues and are Polymorphonuclear neutrophils. usually the first cells on the scene of a bacterial invasion are called: 30) Swelling, redness, heat, and pain are Inflammation all manifestations of 31) The complement system serves to: Attract and enhance the activities of phagocytes 32) The coagulation system serves to: increase blood flow to the area of infection and can also effectively wall off the infection through the production of barrier substances 33) Biochemical Have substantial effects on the activities s known as cytokines serve to: of other cells. 34) Specific proteins produced by cells of the immune system in response to the presence of foreign molecules that Immunoglobulins (Ig) circulate in the serum and are present in secretions such as saliva are called: 35) The antibody that is secreted in various body fluids and primarily protects IgA those body surfaces lined with mucous membranes is: 36) Which stage of infection is Decline characterized by host deterioration and possibly death? 37) Which immune system cells primarily function as antibody producers and Lymphocytes originate from stem cells?

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38) Which immune system cells destroy Natural killer cells infected or malignant host cells? 39) Infectious processes that quickly Acute develop are referred to as ______infections. 40) Infectious processes that develop and slowly progress are known as ______Chronic infections. 41) Proper hand-washing and hygiene procedures by hospital staff are essential Nosocomial in preventing which types of infections? 42) Which one of the following statements They are released upon cell death. is true regarding endotoxins? 43) A bacterium that normally colonizes the skin gains access through a Opportunistic. laceration and causes infection. This type of infection is classified as: 44) An example of antibody-mediated B-cell activation. immunity is: 45) Latent infections are those that: Exist as a silent phase in which the agent is causing no notable effect. 46) Pathogens are able to produce enzymes that directly destroy or Proteases. inactivate antibodies. These enzymes are referred to as: 47) Botulism and tetanus have the ability to interfere with neuromuscular functions. Exotoxins. The toxins they produce are classified as: 48) IgG is the: Second antibody produced when an invading microorganism is initially encountered and the most abundant. 49) IgM is the: First antibody produced when an invading microorganism is initially encountered. 50) IgE is the: Antibody that is associated with various parasitic infections. 51) Air flow in a microbiology laboratory from lower to higher risk areas should be 52) The agency that requires health care Occupational Safety and Health facilities to provide employees with all Administration (OSHA) devices and mechanisms necessary to protect them from the hazards encountered in the laboratory is 53) Procedures such as grinding, create aerosol droplets and should be mincing, vortexing and preparing smears performed only in approved biosafety cabinet

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54) Class I biological safety cabinets protect the environment from contamination by biological agents by filtering the air as it is exhausted from the cabinet

55) Optimal protection of specimen, Class III personnel and environment is accomplished with which class of biological safety cabinet? 56) The method of choice for sterilizing filtration items such as antibiotic solutions, chemicals, radioisotopes, and vaccines that are heat-sensitive is 57) To be sterilized in an autoclave, processed for 30 to 60 minutes at 132C and infectious medical waste should be 15psi pressure 58) The applying moist heat at high autoclave sterilizes material by temperatures and increased pressure 59) The most effective antiseptic agent 10% bleach against blood spills and therefore the antiseptic of choice in laboratories where these agents are likely found is 60) Standard precautions in the clinical specimens that contain blood or microbiology laboratory apply to bodily fluids 61) Standard precautions include using barrier devices to prevent exposure to skin and mucous membranes 62) Mouth pipetting should not be performed in any circumstance in the clinical laboratory 63) Biosafety Level 1 agents require only standard good laboratory techniques 64) Working with Biosafety Level 3 agents laboratory design features that control requires air movement 65) A cleaning solution used on the disinfectant laboratory bench top to kill bacteria that are potentially harmful to humans would be called a(n) 66) A cleaning solution used on the antiseptic venipuncture site to avoid skin contamination of the blood sample is called a(n) 67) Information concerning a chemical found in the manufacturer's material product's health hazards, toxicity, and safety data sheets (MSDS) disposal procedures is 68) The agency that has published a U.S. Environmental Protection Agency guide to hazardous waste reduction is (EPA) 69) The agency that has published CDC

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guidelines known as standard precautions to reduce the risk of disease transmission in laboratories is

70) The agency that has published International Air Transport Association guidelines regarding the packaging of (IATA) biohazardous specimens is known as 71) Class III biological safety cabinets are completely enclosed and have gloves that enable the worker to manipulate the material in the cabinet 72) Minimal protection of specimen, Class I personnel, and environment is accomplished with which class of biological safety cabinet? 73) To be sterilized in an autoclave, processed for 15 minutes at 121 and media or instruments should be 15psi pressure 74) Biosafety Level 2 agents include those that are the common agents of infectious disease 75) Biosafety Level 4 agents require the use of maximum containment facilities 76) A principal role of the clinical Quickly and accurately communicating microbiologist includes? information about the patient in both verbal and written formats. 77) Rejection of inappropriately collected Should be initiated by laboratory or transported specimens? personnel but approved by the nurses or physicians responsible for the care of the patient. 78) The definitive identification of clinically Desirable in most cases; however, significant isolates is? limited identification may sometimes be necessary and helpful. 79) Specimens for microbiologic studies Transported in sealable, leak-proof should be? plastic bags with a separate section for paperwork. 80) Holding media, such as Stuart’s Maintain the viability of microorganisms medium and Amie’s transport medium, present in a specimen. are used to? 81) The best anticoagulant to prevent Sodium polyanethol sulfonate (SPS). clotting of specimens, such as blood, bone marrow, and synovial fluid, which are submitted for recovery of all types of microorganisms, is? 82) Direct examinations such as the Gram To give the physician an early indication of stain serve what purpose? what may be wrong with the patient 83) Which type of media is designed to Nutritive support the growth of a wide range of

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microorganisms? 84) Which type of media is designed to Differential distinguish microorganisms on the basis of certain growth characteristics?

85) Which type of media is designed to Selective support the growth of one group of organisms, but not another, by containing antimicrobials, dyes, or alcohol? 86) An example of a selective medium for colistin and nalidixic acid. gram-positive organisms is? 87) Ambient air, which contains 21% Aerobes oxygen (O2) and a small amount (0.03%) of carbon dioxide (CO2), is the environmental condition that best suits which type of organism?

88) Increased concentrations of CO2 (5% Capnophiles to 10%) and approximately 15% O2 produce an environmental condition that best suits which type of organism?

89) Between 5% and 10% hydrogen (H2), Anaerobes 5% to 10% CO2, 80% to 90% nitrogen (N2), and 0% O2 produce an environmental

90) Reduced O2 (5% to 10%) and Microaerophiles increased CO2 (8% to 10%) produce an environmental condition that best suits 91) Colonies of Streptococcus No discrepancy is present. S. pneumoniae appear alpha-hemolytic on pneumoniae should be alpha-hemolytic blood agar media. Which one of the on blood agar. following statements explains this discrepancy? 92) An example of a beta-hemolytic gram- Staphylococcus aureus. positive organism is? 93) Which specimen is quantitatively Urine plated by using a calibrated loop? 94) Which specimen culture, if positive, Blood should be immediately reported to the clinician? 95) The appropriate storage for a cerebral 37 spinal fluid specimen is ____° C? 96) In microscopy, resolution is defined as Extent to which detail in the magnified the: object is maintained 97) How is contrast in microscopy most By staining techniques commonly achieved?

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98) The 1st step in gram stain sequence is Crystal violet the application of, which is the primary stain? 99) A mordant that is applied after the Gram's iodine primary stain to bond chemically the alkaline dye to the bacterial cell wall is: 100) After which step in the Gram- Gram's decolorizer stain procedure are gram positive bacteria 1st distinguished from gram negative bacteria? 101) The acid fast stain is Mycolic acids specifically designed for bacteria whose cell walls contain: 102) In the Kinyoun acid-fast Increased phenol; heat staining method, what replaces what in the primary stain solution? 103) Of the Fluorescence different types of staining and microscopic techniques, which one of the following is basically the most sensitive? 104) The fluorochrome stain that Auramine can be used to detect mycobacteria is: 105) The fluorochrome stain used to Calcofluor white study a fungus is: 106) What's true about dark field The condenser does not allow light to microscopy? pass directly through the specimen but directs the light to hit the specimen at an oblique angle. 107) Magnifications in excess of Electron 100,000 x are achieved by what microscopy? 108) Bacterial cells with thick The bacterial cells were subjected to the peptidoglycan and numerous teichoic decolorizer too long and were acid cross linkages are Gram stained. overdecolorized. The organisms stain pink. Why? 109) The most critical step in the Gram's decolorizer. Gram stain is the application of the: 110) An organism such as Carbolfuchsin Mycobacterium tuberculosis would absorb which stain in its cell wall? 111) Organisms that have nutritional fastidious needs that are relatively complex and require extra media components to be used for growth are called: 112) The role of the agar ingredient Solidify the medium and provide a in culture medium is to: stable culture surface.

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113) A bacterial colony can be Sufficiently large numbers of a described as: bacterium that can be observable with the unaided eye. 114) Which category of media can Enrichment be described as containing specific nutrients required for the growth of particular bacterial pathogens in a patient specimen? 115) Which category of media can Supportive be described as containing nutrients that support the growth of the most nonfastidious organisms without giving any particular organism a growth advantage? 116) Which category of media can Differential be described as containing some factor or factors that allow colonies of one bacterial species or type to exhibit certain metabolic or culture characteristics that can be used to distinguish them from other bacteria growing on the same agar plate? 117) Which category of media can Selective be described as containing one or more agents that are inhibitory to all organisms except those being sought? 118) In which category of media Selective and differential would MacConkey agar best fit? 119) In which category of media Differential would blood agar best fit? 120) In which category of media Selective would Löwenstein-Jensen medium best fit? 121) Which medium can be Brain-heart infusion (BHI) described as a nutritionally rich medium used to grow various microorganisms, either as a broth or as an agar, with or without added blood? 122) Which medium can be Chocolate described as containing hemoglobin, hemin (X factor), and the co-enzyme nicotinamide adenine dinucleotide (NAD) (V factor)? 123) Which medium can be CNA blood described as suppressing the growth of most gram-negative organisms while

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allowing gram-positive bacteria to grow? 124) Which medium can be Hektoen enteric agar described as containing bile salts and dyes (e.g., bromothymol blue, acid fuchsin) to slow selectively the growth of most nonpathogenic gram-negative bacilli found in the gastrointestinal tract and allow Salmonella spp. and Shigella spp. to grow?

125) Which medium can be MacConkey agar described as containing crystal violet dye to inhibit the growth of gram-positive bacteria and fungi and allows many types of gram-negative bacilli to grow? 126) What name is given to the type Alpha of hemolysis that produces incomplete hemolysis and a greening discoloration of the medium? 127) What name is given to the type Beta of hemolysis that produces complete hemolysis and a clearing of the medium? 128) To read the hemolytic reaction Hold the plate up to the light, and accurately on a blood agar plate, the observe the plate with the light coming technologist must: from behind. 129) Which group of bacteria uses Aerobes oxygen as a terminal electron acceptor and grows well in ambient air? 130) Increased concentrations of Capnophiles carbon dioxide (CO2) (5% to 10%) and approximately 15% oxygen (O2) produce an environmental condition that best suits which type of organism?

131) Reduced O2 (5% to 10%) and Microaerophiles increased CO2 (8% to 10%) produce an environmental condition that best suits which type of organism? 132) A candle jar is used to cultivate Capnophiles which type of bacteria? 133) The most medically important 35° to 37° C bacteria sought in the medical laboratory are cultivated using incubators with temperatures maintained in what range? 134) An oxidase test was performed No discrepancy is present. The correct on two organisms for quality control results are obtained. purposes. Pseudomonas

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aeruginosa andStenotrophomonas maltophilia tested positive and negative, respectively. Which of the following statements explains this discrepancy? 135) A positive pyrrolidonyl Red arylamidase (PYR) test was observed on a species of Enterococcus. What color should be observed for this reaction?

136) Oxidative or fermentative Yellow in the open tube and green in the media were set up on an organism closed tube suspected of being Pseudomonas aeruginosa. What results would be expected? 137) Generation time can be Time required for a bacterial population defined as the: to double.

138) A catalase test was performed The colony may have been from a sheep blood agar plate on a contaminated with sheep red blood colony of streptococci, and bubbling was cells, causing a false-positive result. observed. Which of the following statements explains this discrepancy? 139) Which of the following Campylobacter jejuni organisms grows best at 42º C? 140) Escherichia coli, a member of No discrepancy is present. E. coli is the family Enterobacteriaceae, was resistant to vancomycin. resistant to the antibiotic vancomycin. Which of the following statements explains this discrepancy? 141) What test methodology Bacitracin Susceptibility differentiates group A streptococci from other beta-hemolytic streptococci? 142) What test methodology Bacitracin Susceptibility differentiates staphylococci (resistant) from micrococci (sensitive)? 143) True or False: True In order to determine bacitracin susceptibility, a Taxo A disk is placed on an inoculated agar and zone of inhibition are observed. 144) For bacitracin susceptibility, any zone >10 mm what size of the zone of inhibition is considered susceptible (sensitive)? 145) What are the limitations of Performance depends on the integrity of bacitracin susceptibility? the disk.

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146) What two quality control Streptococcus pyogenes (susceptible) organisms would test positive for Micrococcus luteus (susceptible) bacitracin susceptibility? 147) What two quality control Streptococcus agalactiae (resistant) organisms would test negative for Staphylococcus aureus (resistant) bacitracin susceptibility? 148) What test methodology Bile Esculin Agar differentiates enterococci and group D streptococci from nongroup D viridans streptococci?

149) What color precipitate would dark brown to black form for a positive reaction of bile esculin agar? 150) What are the limitations of bile Some organisms may grow poorly. esculin agar? 151) What quality control organism Enterococcus faecalis (growth, black would test positive on bile esculin agar? precipitate)

152) What two quality control Escherichia coli (growth, no color organism would test negative on bile change) esculin agar? Streptococcus pyogenes (growth, no color change) 153) What two tests differentiate Bile Solubility Test and streptococcus pneumococci (sensitive) Optochin (P Disk) Susceptibility from other alpha-streptococci (resistant)? 154) True or False: True For the bile solubility test, bile or bile salts rapidly lyse pneumococcal colonies on blood agar. 155) What are the limitations of the Old cultures may not have strong bile solubility test? activity. 156) What quality control organism Streptococcus pneumoniae would test positive for the bile solubility test? 157) What quality control organism Enterococcus faecalis would test negative for the bile solubility test? 158) What test methodology CAMP Test differentiates group B streptococci from other streptococci species? 159) True or False: True Listeria monocytogenes produces a positive CAMP reaction.

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160) True or False: True A diffusible hemolytic protein (Christie, Atkins, Munch-Petersen [CAMP] factor) acts synergistically with the beta-lysin of Staphylococcus aureus causing enhanced lysis. 161) If an arrowhead zone of positive hemolysis is observed during the CAMP test, does this show a positive or negative result? 162) What are the limitations of the Some group A streptococci are positive CAMP test? for CAMP. 163) What quality control organism Streptococcus agalactiae (enhanced would test positive for the CAMP test? arrowhead hemolysis) 164) What quality control organism Streptococcus pyogenes (beta would test negative for the CAMP test? hemolysis without enhanced arrowhead formation) 165) What test methodology Catalase Test differentiates catalase-positive organisms and staphylococcus species from catalase-negative streptococcus species? 166) True or False: True For the catalase test, the catalase enzyme converts hydrogen peroxide to water and oxygen, producing bubbles. 167) What are the limitations of the Some organisms (enterococci) appear catalase test? weakly positive. 168) What quality control organism Staphylococcus aureus would test positive for the catalase test? 169) What quality control organism Streptococcus pyogenes would test negative for the catalase test? 170) What test methodology Citrate Utilization identifies the organism’s ability to use sodium citrate as the sole source of carbon? 171) For citrate utilization, the alkaline bacteria that is capable of growing on the medium uses citrate to convert ammonium phosphate into ammonia and ammonium hydroxide, creating an ____ pH which is indicated by a blue color change. 172) What are the limitations of Some organisms will not produce a color citrate utilization? change but will grow. 173) What quality control organism Enterobacter aerogenes (growth, blue

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would test positive for citrate utilization? color) 174) What quality control organism Escherichia coli (little to no growth, no would test negative for citrate utilization? color change) 175) What test methodology Coagulase Test differentiates Staphylococcus aureus (positive) from coagulase-negative staphylococci? 176) During coagulase test, the fibrinogen coagulase or “clumping factor” reacts with ____ in plasma, producing a fibrin clot. 177) What are the limitations of the Positive results can revert back to coagulase test? negative after 24 hours. 178) What quality Staphylococcus aureus control organism would test positive for the coagulase test? 179) What quality control organism Staphylococcus epidermidis would test negative for the coagulase test? 180) What test methodology is used Flagella Stain to visualize the presence and arrangement of flagella for the presumptive identification of motile bacterial species? 181) The flagella stain contains a flagella mordant to better visualize ____. 182) What are the limitations of the Visualization requires expertise and is flagella stain? not an entry-level technique. 183) Match the following quality Escherichia coli – Peritrichous control organisms to their correct flagella stain results. Pseudomonas aeruginosa – Polar Quality control organism: Escherichia coli Klebsiella pneumonia – nonmotile Pseudomonas aeruginosa Klebsiella pneumonia Flagella Stain Results: nonmotile Polar Peritrichous 184) What test methodology is used Indole Production to identify organisms that produce tryptophanase? 185) True or False: True During indole production, tryptophanase will hydrolyze tryptophan to pyruvate, ammonia, and indole.

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186) Kovac’s reagent used for red indole production will produce what color when reacted with indole? 187) The alternative spot indole test blue will produce a ____ color when positive. 188) What quality control organism Escherichia coli would test positive for the Kovac’s method of indole production? 189) What quality control organism Klebsiella pneumoniae would test negative for the Kovac’s method of indole production? 190) What two test methodology Methyl Red and Voges-Proskauer Tests differentiates members of the Enterobacteriaceae family? 191) A positive result for the Methyl red Red Test which detects mixed acid fermentation is indicated by what color? 192) A positive result for the Voges- Red Proskauer Test which detects the ability of an organism to convert the acid products to acetoin and 2,3-butanediol is indicated by what color?

193) For the MRVP Test, is it yes possible for an organism to be positive for one test but not for both of the tests. 194) What are the limitations of the MR test should not be read before 48 Methyl Red and Voges-Proskauer Tests? hours. 195) What quality control organism Escherichia coli would test positive for Methyl Red but negative for Voges-Proskauer Tests? 196) What quality control organism Enterobacter aerogenes would test negative for Methyl Red but positive for Voges-Proskauer Tests? 197) What test methodology Motility Testing determines whether an enteric organism is motile and must possess flagella? 198) For mobility testing, ____ agar semisolid is used to visualize a diffuse zone of growth extending from the line of inoculation. 199) What are the limitations of the Some organisms do not display motility testing? sufficient growth. 200) What quality control organism Escherichia coli would test positive for motility testing?

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201) What quality control organism Staphylococcus aureus would test negative for motility testing? 202) What test methodology Nitrate Reduction determines whether an organism can reduce nitrite? 203) True or False: True Microorganisms capable of reducing nitrite to nitrogen will not turn a color and will produce gas in the nitrate reduction (nitrate to nitrite) test. 204) What are the limitations of Zinc dust is added if broth does not nitrate reduction? become red or no gas is observed. 205) What quality control organism Proteus mirabilis (colorless, gas) would test positive for nitrate reduction? 206) What quality control organism Acinetobacter baumanii (red, no gas) would test negative for nitrate reduction? 207) True or False: True In order to determine optochin susceptibility, a Taxo P disk is placed on an inoculated blood agar plate, incubated, and observed for zone of inhibition.

208) For optochin susceptibility, any zone ≥14 mm what size of the zone of inhibition is considered susceptible (sensitive)? 209) What are limitations of optochin Any zone less than 14 mm is susceptibility? questionable. 210) What quality control organism Streptococcus pneumoniae (susceptible) would test positive for optochin susceptibility? 211) What quality control organism S. pyogenes (resistant) would test negative for optochin susceptibility? 212) What test methodology Oxidase Test determines the presence of cytochrome oxidase activity for oxidase-negative enteric bacteria from other gram-negative rods? 213) The oxidase test determines purple the presence of cytochrome oxidase using tetramethyl-p-phenylenediamine dihydrochloride to indophenol, resulting in what color end product? 214) What are the limitations of the Nickel-base alloy wires that contain oxidase test? chromium and iron may cause a false-

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positive result. 215) What quality control organism Pseudomonas aeruginosa would test positive for oxidase test? 216) What quality control organism Escherichia coli would test negative for oxidase test? 217) What test methodology is used Pyrrolidonyl Arylamidase Test for the presumptive identification of group A streptococci and enterococci? 218) Beta-naphthylamine, a red byproduct of hydrolyzation by L-pyrrolidonyl arylamidase (PYR), will turn ____ in the presence of N,N-dimethylamino cinnamaldehyde reagent. 219) What two quality control Enterococcus faecalis organism would test positive for Streptococcus pyogenes pyrrolidonyl arylamidase test? 220) What quality control organism Streptococcus agalactiae would test negative for pyrrolidonyl arylamidase test? 221) What test methodology Triple Sugar Iron Agar determines whether a gram-negative rod ferments glucose and lactose or sucrose to forms hydrogen sulfide?

222) Triple sugar iron (TSI) agar 10, 10, 1 contains __ parts lactose, __ parts sucrose, and __ part glucose & peptone; and ferrous sulfate. 223) For the triple sugar iron agar, yellow the butt of tube turns ____ if glucose is fermented (acid). 224) For the triple sugar iron agar, yellow the slant of tube turns ____ if lactose or sucrose are fermented (acid). 225) For the triple sugar iron agar, black the tubes turns ____ if hydrogen sulfide is produced. 226) Match the following quality Pseudomonas aeruginosa – K/K control organisms to their correct TSI (alkaline/alkaline) results. Quality control organism: Proteus mirabilis – K/A (alkaline/acid), Pseudomonas aeruginosa hydrogen sulfide Proteus mirabilis Shigella flexneri Shigella flexneri – K/A TSI Results:

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K/A (alkaline/acid) K/K (alkaline/alkaline) K/A (alkaline/acid), hydrogen sulfide 227) What test methodology X and V Factor Tests differentiates Haemophilus species? 228) X, V, or XV strips or disks are confluent placed on ____ inoculation. 229) True or False: True For X and V factor tests, organisms will grow around the disk that provides the appropriate factor for growth. 230) Match the following quality Haemophilus influenza – requires XV control organisms to their correct X and V disk only factor test results. Quality control organism: Haemophilus parainfluenzae – requires Haemophilus influenza V disk; grows around XV and V disks Haemophilus parainfluenzae Haemophilus ducreyi Haemophilus ducreyi - requires X disk; X and V factor test results: grows around XV and X disks requires X disk; grows around XV and X disks requires V disk; grows around XV and V disks requires XV disk only

231) True or False: True Additional tests exist and result in growth, turbidity, or color changes.

232) True or False: True Other test examples include the following: Use of substances as a source of carbon Esculin hydrolysis Fermentation tests Detection of enzymes Growth on specific agars Growth around impregnated disks 233) The most frequent agent of Coagulase-negative staphylococci. nosocomial bacteremia is: 234) The species Staphylococcus aureus. of Staphylococcus, which is one of the most important human pathogens, is: 235) Which group of bacteria is Staphylococcus described as catalase positive and is

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gram-positive cocci that grow facultatively anaerobic and form grapelike clusters? 236) The first identification test Coagulase test. performed on a clinical isolate of gram- positive, catalase-positive cocci would likely be the: 237) The slide coagulase test is a Clumping factor. rapid screening test for the production of: 238) A tube coagulase test was The test should have been read in 1 to 4 performed on catalase-positive, gram- hours in case any hemolysins are positive cocci that were beta hemolytic present. and grew on mannitol salt agar. The tube was checked after overnight incubation and was negative. Which of the following statements explains this discrepancy? 239) The tube coagulase test: Detects extracellular coagulase. 240) In clinical isolates, the most Staphylococcus aureus. likely identification of coagulase-positive, catalase-positive, gram-positive cocci that are penicillin resistant would be: 241) Which virulent and important Staphylococcus aureus human pathogen can also be recovered from the nares, perineum, and other skin sites of healthy people, especially in the hospital setting? 242) The resident human flora, Staphylococcus epidermidis. staphylococcus, which is more likely to cause infections in compromised hosts such as patients with cancer, is:

243) The Staphylococcaceae Staphylococcus saprophyticus. staphylococcus that is more likely to cause uncomplicated urinary tract infections in nonhospitalized hosts, especially sexually active young women, is: 244) Isolates of coagulase-negative novobiocin resistance. Staphylococcus from urinary tract infections can be presumptively identified as S. saprophyticuson the basis of its: 245) Quality control should be Micrococcus and Aerococcus performed on which two organisms to determine the validity of the oxidase reagent? 246) An infected intravenous (IV) Staphylococcus epidermidis.

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catheter tip grew out gram-positive cocci, which were catalase positive and coagulase negative. The zone size of the novobiocin disk measured 18 mm. The most likely organism causing infection is: 247) Which organism is catalase Staphylococcus haemolyticus positive, coagulase negative, pyrrolidonyl arylamidase (PYR) positive, susceptible to novobiocin, urease negative, and beta hemolytic on sheep blood agar? 248) Which organism is best Streptococcus pyogenes described as a catalase-negative, gram positive coccus that is beta-hemolytic on sheep blood agar? 249) Which species of bacteria is S. pyogenes responsible for causing diseases such as rheumatic fever, glomerulonephritis, and exudative pharyngitis? 250) Streptococcus pneumoniae Often carrying an antiphagocytic can be described as: capsule. 251) The colonial morphologic Alpha-hemolytic and bile solubility- features of an organism resembles a positive donut as it ages, and it has a polysaccharide capsule that is responsible for it virulence. What two characteristics describe this organism?

252) The development of acute S. pyogenes rheumatic fever and subsequent valvular heart disease are problems that may be encountered by patients infected with:

253) The development of S. pyogenes glomerulonephritis is a problem that may be encountered by patients infected with: 254) Erythrogenic toxin, S. pyogenes hyaluronidase enzyme, and hemolysins S and O are extracellular products of: 255) The bacterial species that can S. agalactiae be described as able to hydrolyze hippurate, is beta-hemolytic, is a major cause of neonatal meningitis and sepsis, and is a producer of the Christie, Atkins, Munch-Petersen (CAMP) factor is: 256) The CAMP factor is produced S. agalactiae by:

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257) The major etiologic agent of viridans streptococci bacterial endocarditis in the United States is: 258) Enterococci can be described Able to hydrolyze bile esculin. as: 259) The drugs of choice for most Penicillin and an aminoglycoside. enterococcal infections are: 260) The bacterial species that can Enterococcus faecalis. be described as able to grow in 6.5% sodium chloride (NaCl) and 40% bile, is part of the normal fecal flora of animals and humans, is usually nonhemolytic, and is a major cause of nosocomial infections is:

261) Generally speaking, Vitamin B6 nutritionally variant streptococci require what ingredient not found in most conventional media? 262) What morphologic feature is a Hemolytic pattern major consideration in determining an identification scheme for streptococci? 263) Differentiation of the Examination of the morphologic features after pleomorphic strains of streptococci and growth in thioglycollate broth. the similar corynebacteria or lactobacilli can be best accomplished by:

264) Bacitracin, pyrrolidonyl beta-hemolytic arylamidase (PYR), CAMP factor, and hippurate are tests most likely performed on a(n) ______Streptococcus. 265) Optochin, PYR, bile solubility, alpha-hemolytic esculin, and 6.5% NaCl are tests most likely performed on a(n) ______Streptococcus.

266) Media that can be used for 5% sheep blood agar. isolating Bacillus anthracis include: 267) Suspect spore-forming, gram- Bacillus anthracis. positive Bacillus species that is nonhemolytic, nonmotile, and penicillin- susceptible and that produces a wide zone of lecithinase on egg yolk agar can be identified as: 268) Induction of sporulation by urea Bacillus species can be accomplished with _____ agar.

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269) Induction of capsule formation bicarbonate by B. anthracis can be accomplished with _____ agar. 270) Which of the following is Bacillus cereus described as a spore-forming, gram- positive Bacillus that is beta-hemolytic, motile, Voges-Proskauer (VP)–positive, and citrate-positive and causes two types of food poisoning as a result of toxin release? 271) A U.S. Food and Drug Anthracis Administration (FDA)–cleared immunochromatographic test produces a red line on the cassette and can presumptively identify which gram- positive Bacillus that is nonhemolytic and morphologically has a “Medusa head” appearance when grown on 5% sheep blood agar? 272) A gram- The organism produces beta-lactamase, positive Bacillus, which is beta-hemolytic which renders the drug inactive on 5% sheep blood agar, produces a wide zone of lecithinase on egg yolk agar, is nonmotile, and was isolated from the stool of a patient with abdominal pain and watery diarrhea. Because of the patient’s existing immunocompromised state, the physician administered penicillin as the antibiotic therapy. The patient’s condition did not improve after 7 days of treatment. Which one of the following statements explains the reason for the antibiotic failure? 273) Which of the following types of Gastrointestinal anthrax occurs after ingesting the spores and affects the abdominal or oropharyngeal area? (Patients usually die from toxemia and overwhelming sepsis.) 274) A patient diagnosed with Ciprofloxacin Bacillus anthracis is allergic to penicillin. Which antibiotic can be given that will be therapeutically effective? 275) Enzyme-linked immunosorbent Anthracis assays (ELISAs) are available that can serologically identify which Bacillus

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species? 276) Not including organisms in Pseudomonas. the Enterobacteriaceae family, the second most common gram-negative bacilli encountered in clinical specimens are: 277) Production of exotoxin A and Pseudomonas aeruginosa several proteolytic enzymes and hemolysins are factors that contribute to the pathogenicity of which organism? 278) The disease referred to Burkholderia pseudomallei as melioidosis is caused by which one of the following? 279) A convenient and reliable Oxidase, triple sugar iron (TSI) slant, identification scheme for Pseudomonas growth at 42° C on Mueller-Hinton agar aeruginosa involves which of the or trypticase soy agar following conventional tests? 280) An organism described as Pseudomonas aeruginosa oxidase-positive, (K/NC) on TSI media, growth at 42° C, and produces a bright bluish-green pigment on Mueller-Hinton agar is 281) Which two organisms should Brevundimonas be used to determine the validity of urea vesicularis and Ralstonia pickettii agar for quality control purposes? 282) Which species Burkholderia cepacia of Burkholderia is the one most commonly found in clinical specimens? 283) Which best Medical devices describes the source of Burkholderia cepacia infections? 284) Which organism exhibits Pseudomonas pseudomallei bipolar staining on the Gram stain, which resembles a “safety-pin” appearance? 285) Oxidative–fermentative base– Burkholderia cepacia polymyxin B–bacitracin-lactose (OFPBL) media is the best media to use to isolate which one of the following organisms from the sputa of patients with cystic fibrosis?

286) What species causes Pertussis Bordetella (whooping cough), an epidemic disease that is a highly contagious, acute infection of the upper respiratory tract? 287) What is the best description of close contact with animals

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the mode of transmission of Bordetella bronchiseptica ? 288) What are important identifying Gram-stain morphologic features, characteristics of Bordetella? motility, and flagellar placement 289) Which two organisms should Achromobacter be used to set up a quality control to piechaudii and Bordetella determine the validity of cetrimide agar? bronchiseptica 290) What is the best description of contaminated fluids or medical solutions the mode of transmission of Achromobacter denitrificans? 291) What are Achromobacter, nonglucose utilizers. Alcaligenes, and Bordetella all known as? 292) Which of the following The habitats vary from the soil and water statements best describes the habitats environment to the upper respiratory tract of of Achromobacter, various mammals. Alcaligenes, and Bordetella? 293) What is the organism most Achromobacter. frequently associated with various infections in humans? 294) What is the biochemical Oxidase-positive, motile, and rapid description of Bordetella bronchiseptica? urease–positive. 295) What is the biochemical urease-positive and has a fruity odor description of Myroides? 296) Profuse watery diarrhea (i.e., Cholera toxin (CT) “rice water stools”), leading to dramatic fluid loss, severe dehydration, and hypotension that frequently leads to death, is the hallmark of which toxin activity? 297) Stool specimens suspected of vibrio containing which of the following enteric pathogens should be collected and transported only in Cary-Blair medium because buffered glycerol saline is toxic for this bacterium? 298) The selective medium, vibrio thiosulfate citrate bile salts sucrose (TCBS) agar, is especially formulated for isolating what pathogen from stool cultures? 299) The reagent used in the “string Sodium deoxycholate test” is:

300) Vibrio cholera and V. alginolyticus appear what color on TCBS yellow

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agar? 301) Colonies growing on modified oxidase cefsulodin-irgasan-novobiocin (CIN) agar appear to be either Aeromonas spp. or Yersinia enterocolitica. Which test should be performed to differentiate between these two organisms? 302) Vibrio Check the pH to ensure that it is 8.6 cholerae and Photobacterium damsela are used to perform quality control on TCBS agar. After overnight incubation, no growth is observed. What is the next course of action? 303) An organism suspected of The oxidase test should be performed being one of the Vibrio spp. grew on on a sheep blood agar plate to avoid MacConkey agar. To determine whether it false-negative results. was a vibrio cell or in the Enterobacteriaceae family, an oxidase test was performed on the colony. The results of the oxidase test, however, were negative. Which one of the following statements explains this discrepancy? 304) Which of the following Habitats are mostly soil and water statements best describes the habitats environment of Vibrio spp., Aeromonas spp., Plesiomo nas shigelloides, andChromobacterium violaceum? 305) The primary habitat Brackish or marine water. for Vibrio spp. is: 306) A vibriostatic test using 0/129 aeromonads (2,4-diamino-6,7-diisopropylpteridine)– impregnated disks differentiates vibrio cells, which are susceptible, and ______, which are resistant 307) Which organism, which is Beta-hemolytic and is a nonlactose oxidase positive, does not grow on TCBS fermenter agar, has the ability to decarboxylate lysine and ornithine but cannot utilize arginine, and would have the following colonial characteristics on sheep blood agar and MacConkey agar? 308) Which of the following species A. veronii biovar veronii of Aeromonas is oxidase-positive, sucrose-positive, and can decarboxylate ornithine?

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309) The transmission of Vibrio spp. ingestion of contaminated seafood or to humans is by: water 310) Transmission ingestion of contaminated seafood or of Aeromonas spp. to humans water

311) Transmission of Plesiomonas ingestion of contaminated seafood or shigelloides to humans is by: water 312) Transmission exposure of disrupted skin to of Chromobacterium violaceum to contaminated water humans is by: 313) The drug of choice to treat tetracycline patients with Vibrio cholera is: 314) To determine the validity of 0% V. parahaemolyticus and V. cholerae sodium chloride (NaCl) broth, which two organisms should be used for quality control purposes? 315) Which organism appears green V. vulnificus on TCBS agar and is halophilic? 316) How can true cocci, such as Subject the bacterium to noninhibitory most Neisseria spp. concentrations of penicillin. and Moraxella (Branhamella) catarrhalis, be differentiated from morphologically similar Moraxella species by? 317) What is the species M. catarrhalis of Moraxella that is most commonly associated with human infections, primarily of the respiratory tract? 318) In Gram-stained It will appear as either gram-negative preparations, what will Moraxella coccobacilli or short, broad rods that atlantae appear as? tend to resist decolorization and may appear gram-variable. 319) In Gram-stained preparations, It will appear as coccobacilli or medium- how will Moraxella lacunata appear as? sized rods. 320) What is the virulence of this It is attributed to as something unknown. organism(s), which is transmitted via a dog bite, is attributed to? 321) Quality control should be M. nonliquefaciens and M. canis performed on which two organisms to determine the validity of deoxyribonuclease (DNase) media? 322) How can testing for It can be best performed by the ability to utilize differentiation acetate. of Moraxella nonliquefaciens and M. osloensis can best be performed by? 323) How can testing for It can best be performed by the ability to differentiation of Moraxella lacunata from liquefy serum.

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other Moraxella species can best be performed by: 324) Which organism appears clear M. canis on MacConkey agar and resembles some colonies of the Enterobacteriaceae family? 325) Which of the following tests Catalase can be performed to differentiate the two subspecies of Neisseria—elongata and glycolytica? 326) With one exception, species of Hemin and nicotine adenine the genus Haemophilus require which of dinucleotide (NAD) the following media ingredients for in vitro growth? 327) Among H. influenzae strains, capsular characteristics group designations (e.g., type b) are based on: 328) Chancroid is the sexually H. ducreyi transmitted disease caused by: 329) Which of the following media Chocolate agar provides the factors necessary for the growth of Haemophilus spp.? 330) In a phenomenon known as Staphylococcus aureus satelliting, tiny colonies of Haemophilus spp. may be observed growing on sheep blood agar close to colonies of: 331) In a phenomenon known as NAD satelliting, tiny colonies of Haemophilus spp. may be observed growing on sheep blood agar close to colonies of bacteria that can produce: 332) Haemophilus ducreyi requires Mueller-Hinton–based chocolate agar, what special media to grow? supplemented with 1% IsoVitaleX and vancomycin 333) The sputum H. influenzae of a 75-year-old man with chronic lung infections yields the following: • Many gram-negative coccobacilli in Gram stain; X and V factors required for growth; Nonhemolytic on rabbit blood agar. The organism can be identified as: 334) Growth of most Haemophilus 5% to 10% carbon dioxide (CO2) species in culture is enhanced by: 335) Performance of the “factor inoculation of unsupplemented media requirement test” for Haemophilus with a light suspension of the organism

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involves the: and placement of X and V factor disks on the agar surface

336) Isolates from cerebrospinal H. influenzae fluid (CSF) or respiratory tract specimens that are gram-negative coccobacilli, grow on chocolate agar in CO2 but not on blood agar, and are porphyrin-negative and nonhemolytic on rabbit or horse blood may be identified as: 337) H. influenzae can be positive; xylose fermentation distinguished from H. aegyptius by its _____ test for _____. 338) A 6-year-old boy was Growth requirements require both X and diagnosed with purulent conjunctivitis V factors; the organism is hemolytic on caused by a species of Haemophilus. rabbit blood. What would the biochemical profile of the organism be? 339) Although a useful test in the the increased use of H. influenzae, type past, the particle agglutination assay for b, vaccination the detection of H. influenzae, type b, capsular polysaccharide antigen is no longer reliable because of: 340) Of the following media, which Chocolate agar provides the NAD necessary for the growth of Haemophilus spp.? 341) Isolates from an ear swab that H. influenzae are gram-negative coccobacilli grow on chocolate agar in CO2 but not blood agar, require both X and V factors for growth, and are nonhemolytic on rabbit or horse blood may be identified as: 342) Isolates from CSF that are Haemophilus parainfluenzae gram-negative coccobacilli, grow on chocolate agar in CO2 but not blood agar, require factor V but not X, and are nonhemolytic on rabbit or horse blood may be identified as: 343) To increase the sensitivity of centrifuged before staining direct Gram-stain examination of body fluid specimens, the specimens are usually 344) Which of the following Aggregatibacter aphrophilus opportunistic organisms is associated

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with slowly progressive subacute bacterial endocarditis? 345) The virulence of this organism, capsular factors which causes chancroid, is most likely attributed to:

346) The majority of human contamination of food, milk, or water with infections with Campylobacter species animal feces. are caused by: 347) Campylobacter spp. can small curved or seagull-winged gram- sometimes be detected by direct Gram- negative bacilli. stain examination of fecal sample, which would reveal many: 348) Curved, microaerophilic, gram- Helicobacter negative rods, with most species having strong urease activity and the majority of which colonize mammalian stomachs or intestines, describe which group of bacteria? 349) Virulence determinants urease enzyme of Helicobacter pylori include: 350) Antimicrobial therapy metronidazole, bismuth salt, and for Helicobacter pylori infection consists tetracycline of: 351) A gram-negative, spiral-shaped C. jejuni subsp. jejuni. organism is isolated from a stool sample that was hippurate-positive, catalase- positive, susceptible to nalidixic acid, and resistant to cephalothin. The organism can be identified as: 352) Ensuring that all foods derived Campylobacter. from animal sources are thoroughly cooked, all milk is pasteurized, and all drinking water is chlorinated are ways to avoid becoming infected with: 353) Campylobacter 42º C under microaerobic conditions jejuni subsp. jejuni grows best at what conditions? 354) Which of the following genes babA may attribute to the virulence of Helicobacter pylori by encoding for outer membrane proteins that mediate adherence to a specific blood group

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antigen on the surface of gastric epithelial cells? 355) Which organisms should be C. jejuni subsp. jejuni and C. coli used to perform quality control on hippurate reagent?

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