MLS 301 All available practice quizes
Which of the following statements about enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is false? It is capable of fermenting sorbitol It is transmitted via contaminated undercooked meat It is capable of causing hemolytic uremic syndrome (HUS) It produces Shiga-like toxin
It is capable of fermenting sorbitol
All of the following are true about Bacillus cereus except: Answers: It is gram negative It forms spores It is aerobic or facultative aerobic The preformed toxin from the organism can cause food poisoning
It is gram negative
All of the following are true about Bacillus anthracis EXCEPT: Answers: It is grouped in pairs It is rod shaped It is grouped in chains It is gram positive
It is grouped in pairs
In 2001 there was a resurgence of anthrax linked to mail. Which of the following features of Bacillus anthracis resulted in the bioterrorist attacks? Answers: The ability of the organism to live in an environment without oxygen. Its ability to form spores Its ability to grow in minimal media Its ability to survive in low temperature environments
Its ability to form spores
Clarithromycin, is a: Answers: Quinolone Macrolide Beta Lactam Tetracycline
Macrolide
In Gram-staining, iodine is used as a______________ Fixative Mordant Solublizer Stain
Mordant
he best procedure to differentiate Listeria monocytogenes from Corynebacterium spp. is: Answers: Catalase Motility at 22 degrees Celsius Motility at 35 degrees Celsius Gram Stain
Motility at 22 degrees Celsius
Haemophilus is typically described as smelling like: Answers: Freshly plowed fields Old socks Grapes Musty basement
Musty basement
Which clinical presentation is most consistent with Clostridium perfringens infection? Droopy lids and diplopia Lockjaw and hypertonia Myonecrosis and gas gangrene Profuse diarrhea and pseudomembranous colitis
Myonecrosis and gas gangrene
___________+ ____________+ chain of AA= peptidoglycan layer of cell wall
NAG + NAM
Which of the following antibiotics is the first-line treatment for methicillin-sensitive Staphylococcus aureus? Penicillin Vancomycin Nafcillin Tobramycin
Nafcillin
The anaerobic bacteria typically found in the respiratory tract are gram __________ Answers: Negative Positive
Negative ex ecoli
_________________ is the branch of taxonomy concerned with the assignment of names to taxonomic groups in agreement with published rules Identification Nomenclature Classification Polyphasic Arrangement
Nomenclature
Which of the following best describes Staphylococcus saprophyticus? Alpha Hemolytic on Blood Agar Novobiocin Resistant Coagulase Negative Catalase Negative
Novobiocin Resistant
A gram stain of organisms on Loeffler agar showed pleomorphic gram-positive bacilli. The organism should be subcultured to: Answers: BAP CHOC MAC Potassium Tellurite
Potassium Tellurite
By what mechanism does Staphylococcus epidermidis adhere to the host cell? Lysis of red blood cells Conversion of hydrogen peroxide to water Prevention of complement Production of polysaccharide biofilm
Production of polysaccharide biofilm
___________ are antibacterial drugs that affect DNA replication by targeting topoisomerases II (DNA gyrase) and IV. Answers: Aminoglycosides Beta Lactams Quinolones Macrolides
Quinolones
What are Quinolones?
Quinolones are antibacterial drugs that affect DNA replication by targeting topoisomerases II (DNA gyrase
Which of the following is considered a primary drug for the treatment of Mycobacterium tuberculosis? Answers: Rifampin Kanamycin Rifabutin Ethionamide
Rifampin
Which of the following organisms is the most common cause of neonatal meningitis Streptococcus pyogenes Streptococcus agalactiae Group D Streptococcus Staphylococcus aureus
Streptococcus agalactiae
The optichin disk is used for the identification of: Answers: Haemophilus influenzae Group A Strep Streptococcus pneumoniae Alpha Hemolytic Strep
Streptococcus pneumoniae
Streptolysin O vs Streptolysin S:
Streptolysin O: oxygen labile and antigenic (ASO titer) Streptolysin S: oxygen stabile and non-antigenic
Macrolides such as erythromycin, clarithromycin, and azithromycin target the _____ subunit
50S
Enterohemorrhagic Escherichia coli (EHEC) is also known as O15___:H___ strain
7,7
Most pathogenic bacteria grow best at a neutral pH (7.0-______)
7.5
Which of the following is most likely caused by an enterococcal infection? Answers: 75 year old nursing home female with pyelonephritis 62 year old male with pneumonia producing a brown sputum 21 year old male presents with small, painful ulcerations on shaft of penis 5 day old female presents with bacterial meningitis
75 year old nursing home female with pyelonephritis
_______ Percent of bacteria present in the mouth are anaerobic. Answers: 10% 30% 60% 90%
90%
Which of the following best describes cutaneous anthrax? Answers: A lesion that is flat, red, with a honey-colored crust A vesicular ulceration with a central black crust A well defined area of redness and induration with a central head A hypopigmented flat lesion
A vesicular ulceration with a central black crust
Which of the following characteristics help to differentiate Streptococcus agalactiae from Group A Streptococcus? Ability to grow in bacitracin-treated media Beta Hemolysis Gram Positive Optochin Sensitivity
Ability to grow in bacitracin-treated media
Which type of metabolic activity yields more energy? Answers: Aerobic Respiration Anaerobic Respiration
Aerobic Respiration
hich pattern of hemolysis do Streptococcus pneumoniae and Streptococcus viridans display? Answers: Alpha Hemolysis Beta Hemolysis Delta Hemolysis Gamma Hemolysis
Alpha Hemolysis
This antibiotic class interacts with a specific region of the 16S RNA in the 30S ribosomal subunit. Examples are streptomycin and kanamycin. Answers: Aminoglycosides Tetracyclines Macrolides Quinolones
Aminoglycosides
Identify the antibiotic that should be selected to treat a UTI caused by Enterococcus spp. Answers: Penicillin Ampicillin Vancomycin Novobiocin
Ampicillin
The etiologic agent of botulism is: Normal oral flora Highly Motile Non-spore-forming An exotoxin producer
An exotoxin producer
The combination of two antimicrobial agents worsening the outcome is an example of: Answers: Synergy Antagonism Indifference
Antagonism
A 15-year-old boy stepped on a piece of glass at the beach and presents to the ER. The physician who examines the patient observes that the wound was full of sand and irrigates it with saline. After rinsing which type of agent should the doctor consider cleaning around the wound with? Disinfectant Antiseptic Antiviral
Antiseptic
Corynebacterium diphtheriae treat with , _____________Penicillin or Erythromycin Listeria monocytogenes treat with Ampicillin Erysipelothrix rhusiopathiae treat with __________
Antitoxin. Penicillin
Which of the following best represents an effective strategy for preventing foodborne Listeriosis? Answers: Avoiding canned soup Avoiding soft cheese Avoiding cold cuts Avoiding undercooked meats Question
Avoiding soft cheese
Which organism commonly causes food poisoning by consumption of foods containing excessive populations of organisms or preformed enterotoxin? Answers: Salmonella enteritidis Shigella sonnei Bacillus cereus Escherichia coli
Bacillus cereus
Fluid from a cutaneous black lesion was submitted for routine bacterial culture. After 18 hours of incubation at 35 degrees Celsius, there was no growth on MAC, but 3+ growth on sheep blood agar. The colonies were non-hemolytic, non-motile, 4-5mm in diameter and off white with a ground glass appearance. Each colony had an irregular edge with comma-shaped outgrowth that stood up like "beaten egg whites" when gently lifted with an inoculating needle. A Gram stain of a typical colony showed large, gram-positive rectangular bacilli. The organism is most likely: Answers: Clostridium perfringes Aeromonas hydrophila Bacilus anthracis Mycobacterium marinum
Bacilus anthracis
A strict anaerobe that produces terminal spores is: Clostridium tetani Corynebacterium diptheriae Bacillus anthracis Propionbacterium acnes
Clostridium tetani
Which of the following physical characteristic or biochemical result is not consistent with Mycobacterium tuberculosis? Answers: It is positive for niacin accumulation. Colonies are typically yellow. The organism reduces nitrate to nitrite. The organism is positive for catalase production.
Colonies are typically yellow.
Pseudmonas aeruginosa is a non-lactose fermenting gram negative rod. Based upon this information, what color should the organism be when grown on MAC agar? Answers: White Colorless Pink Yellow
Colorless
Certain types of bacteria are able to produce their own food. An example of this would be: Answers: Staphylococcus aureus Thermus aquaticus Cyanobacteria spp. Streptococcus pneumoniae
Cyanobacteria spp.
staphylococcal resistance to clindamycin is occasionally inducible, (meaning it is detectable in vitro only when the bacteria are also exposed to erythromycin). Which test could be performed in the lab to detect the inducible resistance? CAMP Test D Test Clindamycin Solubility Test VRSA Sensitivity Test
D Test
According to current taxonomic practice, what is the highest level of grouping organisms? Kingdom Domain Phylum Species
Domain
Which blood agar result is most associated with Clostridium perfringens? Green Halo Double zone of beta hemolysis No Hemolysis Total Clearing
Double zone of beta hemolysis
Streptococcus pneumoniae is a fastidious organisms and will not grow on all types of bacterial culture media. A 5% sheep's blood agar plate is typically the culture medium of choice. What type culture medium is the blood agar plate? Answers: Minimal Medium Selective Medium Enriched Medium Nutrient Medium
Enriched Medium
Identify the biochemical difference between Enterococcus spp. and Group D Streptococcus. Answers: Group D Streptococcus is bile esculin negative and Enterococcus spp is bile esculin positive. Enterococcus spp. can grow in 6.5% NaCl and Group D Streptococcus cannot. Enterococcus spp. is PYR negative and Group D Streptococcus is PYR positive. Enterococcus spp. is catalase positive and Group D Streptococcus is catalase negative.
Enterococcus spp. can grow in 6.5% NaCl and Group D Streptococcus cannot.
67 year old male presents to the clinic with an erythematous rash on the right side of his face. The lesion is slightly raised, sharply demarcated, and about 3 centimeters in diameter. What is the most likely diagnosis? Pharyngitis Acute rheumatic fever Impetigo Erysipelas
Erysipelas
Anaerobes that exist outside the bodies of animals are referred to as: Answers: Exogeneous anaerobes Endongenous anaerobes Aerotolerant anaerobes Strict anaerobes
Exogeneous anaerobes
E. coli is oxidase positive True False
False
Shigella spp. is an opportunistic pathogen. True False
False
True or False: All organism that are visualized microscopically are viable cells. Answers: True False
False
The food that is typically associated with Bacillus cereus food poisoning is: Answers: Honeydew Melon Undercooked Hamburger Macaroni Salad Fried Rice
Fried Rice
Select the following manifestations that typically clues that an anaerobic infection is present: Answers: Gas Production Tissue Necrosis Foul Smell Black Discharge
Gas Production Tissue Necrosis Foul Smell Black Discharge
Which type of bacteria has a thicker peptidoglycan layer? Gram Positive Gram Negative
Gram Positive
Exogeneous anerobic infections are typically caused by: Answers: Gram positive organisms Gram negative organisms
Gram positive organisms
Which of the following best characterizes Escherichia coli? Gram-positive lactose fermenting rod Gram-negative lactose fermenting rod Gram-positive non-lactose fermenting rod Gram-negative non-lactose fermenting rod
Gram-negative lactose fermenting rod
Which of the following best describes Staphylococcus aureus Gram-negative bacillus Gram-negative diplococci Gram-positive bacilli Gram-positive cocci
Gram-positive cocci
What is Erysipelas?
Superficial red, raised skin rash. Painful, and hardened. Fat tissue is very susceptible to infection. Fever, shaking, chills, vomiting.
A 43 year old man presented to the urgent care five hours after eating a beef stew that his wife made. He complained of an acute onset of severe abdominal pain and bloody diarrhea. The doctor strongly suspects food poisoning caused by Clostridium perfringens. What type of the organism would you expect to be the cause of the illness? Type A Type B Type C Type D
Type C
Escherichia coli is the number one cause overall of which of the following types of infection? Meningitis Pneumonia Bone Infection UTI
UTI
Complete the statement below: Resistance of enterococci to glycopeptides such as _____________ and teicoplanin was first described in the late 1980s. In the United States approximately 14% of E. faecalis and 87% of E. faecium isolated from blood are _____________ resistant. VRE have become a global problem. Answers: Penicillin Vancomycin Kanamycin Meropenem
Vancomycin
Mycobacteria are slender, slightly __________ or straight, rod-shaped organisms. strictly ______________
curved, aerobic
L. monocytogenes(cantaloupe) is associated with Outbreaks are usually associated with cheese or ________meats.
deli
Umbilicate (___________center, concave)
depressed
The identification of an isolate as C. diphtheriae _______ mean that the patient has diphtheria. Have to identify diphtheria toxin
does not
E. rhusiopathiae is associated with Individuals whose work involves handling ___________and animal products. MOT= _______ or scratches on skin
fish, cuts
CHOC agar does not display ________ because the RBCs in the medium were lysed during media preparation.
hemolysis
L. monocytogenes is: ____________hydrolysis positive Catalase positive Bile esculin hydrolysis_______________
hippurate , positive
On EMB agar, E. coli: Is orange is metallic green is pink is black
is metallic green
You treat TB with ___________and rifampin
isoniazid
Most enteric pathogens do not ferment _________
lactose.
Mycobacteria have a high __________ content in its cell walls that makes it acid fast.
lipid
α-Hemolysis is partial ______- of RBCs in an SBA plate around and under the colony that results in a _________ discoloration of the medium.
lysis, green
E. coli remains one of the most common causes of septicemia and _______________among neonates
meningitis
Listeria monocytogenes Disease is of major concern in Pregnancy, ________________ and ____________________ patients
newborns, immunosuppressed patients
Most strains of M. bovis are ___________negative and do not reduce nitrate
niacin
B. cereus(fried rice) is a relatively common cause of food ______________. Foods= meat or poultry, vegetables, and pasta. You get diarrheal syndrome The incubation period of 8 to 16 hours. caused by two distinct __________________-
poisoning ,enterotoxins
B. anthracis is catalase _________ and grows aerobically or anaerobically. B. anthracis is generally susceptible to ___________ Non-hemolytic, non-motile
positive, penicillin
Umbonate (________ or bulging center, convex)
raised
C. diphtheriae causes two different forms of disease in humans: __________and cutaneous diphtheria
respiratory
C. diphtheriae is a gram positive ________ that is _______ shapped.
rod, club
the uptake of DNA by one cell, from cells in its the surroundings is ________
transformation
______________(PBP) crosslinks the peptidoglycan layer of cell wall
transpeptidase
Koch's Postulate
1. The microorganism must be seen in every case of the disease and be free from health cells 2. The microorganism must be isolated and grown in a pure culture 3. The microorganisms when introduced into a healthy person causes disease 4. Must be able to Isolate organism again from infected host
Match the organism with the appropriate temperature range: Question Psychrophiles Mesophiles Thermophiles
10 - 20 °C c. 50 - 60 °C b. 20 - 40 °C
It is your first day working in a research laboratory and your PI (Primary Investigator) asks you to autoclave culture media for an experiment that will be performed tomorrow. In order to ensure that all microorganisms and endospores are destroyed, which of the following autoclave settings should be used? 100ºC for 60 Minutes 121ºC, 15 PSI for 15 Minutes 72ºC for 15 Seconds 212ºC 10 PSI for 15 Minutes
121ºC, 15 PSI for 15 Minutes
Aminoglycosides interact with a specific region of the ______RNA in the 30S ribosomal subunit.
16S
What is the length of an average bacterial cell? 1μm 3nm 10μm 1mm
1μm
How long is the generation time for the average bacterial cell? Answers: 5 minutes 30 minutes 1 hour 24 hours.
30 minutes
Tetracycline compounds target the ___________- ribosomal subunit and are represented by tetracycline, doxycycline.
30S
Pregnant women should be screened for GBS at: 20 Weeks 6 Weeks 36 Weeks 10 Weeks
36 Weeks
Which of the following combinations of biochemical reactions best describes Group B Streptococci Bacitracin Sensitive, CAMP Positive, Hippurate Positive, Alpha Hemolytic Bacitracin Resistant, CAMP Positive, Hippurate Positive, Beta Hemolytic Bacitracin Resistant, CAMP Negative, Hippurate Positive, Beta Hemolytic Bacitracin Sensitive, CAMP Positive, Hippurate Negative, Beta Hemolytic
Bacitracin Resistant, CAMP Positive, Hippurate Positive, Beta Hemolytic
The type of hemolysis that is typically associated with Staphylococcus aureus is: Alpha Hemolysis Beta Hemolysis Gamma Hemolysis Delta Hemolysis
Beta Hemolysis
Enterococcus spp. are positive for which of the following tests (Select all that apply). Answers: Bile Esculin Catalase 6.5% NaCl Coagulase
Bile Esculin 6.5% NaCl
Viridans streptococci can be differentiated from Streptococcus pneumoniae by: Answers: Alpha Hemoylsis Morphology Catalase Bile Solubility
Bile Solubility
Which of the following statements are true regarding the identification of Corynebacterium diphtheriae? Answers: Double zone of beta hemolysis Black colonies on cystine tellurite agar Clustered rods on gram stain Gram variable staining
Black colonies on cystine tellurite agar
Initial antimicrobial therapy typically used ___________ spectrum antibiotics. Answers: Narrow Broad
Broad
Mycobacterium tuberculosis is specifically stained with: Answers: Crystal Violet 1% Acid Fuchsin Carbol Fuchsin Methylene Blue
Carbol Fuchsin
All bacteria have certain essential nutritional requirements for growth. Identify all of the requirements. Answers: Carbon Hydrogen Nitrogen ATP CaMP Oxygen Carbon Dioxide
Carbon Nitrogen ATP
Select the expected biochemical and antibiotic testing results for Staphylococcus epidermidis Novobiocin Resistant Catalase Positive Coagulase Positive Bacitracin Susceptible
Catalase Positive
Select the expect biochemical results for Bacillus anthracis Answers: Beta Hemolytic Catalase Positive Non-Motile Resistant to penicillin
Catalase Positive Non-Motile
Which of the following test results would you expect for Staphylococcus aureus? Catalase Positive, Beta Hemolytic, Coagulase Negative Catalase Positive, Gamma Hemolytic Coagulase Positive Catalase Positive, Beta Hemolytic, Coagulase Positive Catalase Negative, Beta Hemolytic, Coagulase Positive
Catalase Positive, Beta Hemolytic, Coagulase Positive
Which of the following statements is true? When grown on mannitol salt agar, Staphylococcus aureus will turn the agar pink. Staphylococcus aureus uses altered beta lactam rings to develop penicillin resistance Staphylococcus aureus is coagulase negatve AND beta hemolytic when grown on a blood agar plate. Clindamycin or Bactrim can be used to treat staphyloccoal skin infections.
Clindamycin or Bactrim can be used to treat staphyloccoal skin infections.
The reverse CAMP test, lecithinase production, double zone of hemolysis, and Gram stain morphology are all useful criteria in the identification of: Clostridium perfringes Streptococcus agalactiae Propionbacterium acnes Bacillus anthracis
Clostridium perfringes
Which of the following is the best description of Streptococcus pyogenes? Group B streptococcus, gram-positive, bacitracin-resistant Group B Streptococcus, gram-positive, bacitracin-sensitive Group A Streptococcus, gram-positive, bacitracin-resistant Group A streptococcus, gram-positive, bacitracin-sensitive
Group A streptococcus, gram-positive, bacitracin-sensitive
A β-hemolytic, catalase-negative, gram-positive coccus is found to be resistant to bacitracin and sulfamethoxazole. Which of the following is a likely presumptive identification? Group A streptococci Group B streptococci Group D streptococci Enterococci
Group B streptococci
Which feature distinguishes Erysipelothrix rhusiopathiae from other clinically significant, non-spore forming gram-positive, faculatively anaerobic bacilli? Answers: H2S Production More motile at 22 C than 37 C Tumbling Motility Beta Hemolysis
H2S Production
B cerus has __________on BAP, Motile Resistant to ____________
Hemolysis, penicillin
Bacteria that require an organic source of carbon, such as glucose, and obtain energy by oxidizing or fermenting organic substances are called: Answers: Autotrophs Phototrophs Chemolithotrophs Heterotrophs
Heterotrophs
Ideally, doctors would prefer to treat their patients with antibiotics that have a _________ therapeutic index. Answers: High Low
High
Infant botulism is typically associated with the consumption of: Pickles Honey Rice Gravy
Honey
The enzyme that is responsible for degrading human tissue by destroying the polysaccharide that holds cells together is called: TSST-1 Exfoliative Toxin DNAse Hyaluronidase
Hyaluronidase
By which mechanism of action does Staphylococcus aureus cause rapid onset food poisoning? Binding of MHC class II and T cell receptors Ingestion of preformed toxin Chronic bacterial colonization of the gallbladder Survival in gastrointestinal tract via acid stability
Ingestion of preformed toxin
________________ is the most dangerous method of transmission for Bacillus anthracis. 85% mortality rate
Inhalation
The appropriate sterilization technique to sterilize surgical gloves would be: Ionizing Radiation Dry Heat Iodine Non-Ionizing Radiation
Ionizing Radiation
Match the antigen with the correct description. O Antigen H Antigen K Antigen A. Somatic antigen: This is a heat-stable antigen located on the cell wall B. Capsular antigen: This is a heat-labile polysaccharide found only in certain encapsulated species. C. Flagellar antigen: This is a heat-labile antigen found on the surface of flagella, structures responsible for motility
O Antigen H Antigen K Antigen A, C, B
Cutibacterium is typically found Answers: In the mouth On the skin In the GI tract In the GI tract
On the skin
Beta Lactam antibiotics bind to _______ which inhibits the formation of peptidoglycan. Answers: CDII and CDIV ECORIs PBPs Trans-ALAs
PBPs
A patient tests positive for strep throat. Which of the following antibiotics would be primary treatment choice? Clindamycin Bactrim Penicillin Vancomycin
Penicillin
The appropriate treatment for Erysipelothrix rhusiopathiae is: Answers: Penicillin Ampicillin Streptomycin Vancomycin
Penicillin
____________ cells are subpopulations of bacteria deep in a biofilm (discussed later) that can differentiate into a phenotypically resistant state.When conditions are favorable for growth these bacteria will resume growth. Answers: Resistant Dormant Persister Mutated
Persister
Characteristics necessary for the definitive identification of Mycobacterium tuberculosis are: Answers: Buff color, slow growth at 37 degrees Celsius, niacin production positive, nitrate reduction-negative. Rough colony, slow growth at 37 degrees Celsius, non-pigmented Rough, non-pigmented colony, cording positive, niacin production negative, catalase negative Rough, non-pigmented colony, slow growth at 37 degrees Celsius, niacin production positive, nitrate reduction-positive.
Rough, non-pigmented colony, slow growth at 37 degrees Celsius, niacin production positive, nitrate reduction-positive.
E. rhusiopathiae produces three types of disease Erysipeloid, __________, , Diffuse cutaneous disease
Septicemia:
Organisms that have distinct antigenic characteristics can be divided into groups called: Morphovars Biovars Serovars Euvars
Serovars
Which of the following statements about viruses is FALSE? Viruses are aceullular, lack a cytoplasmic membrane and are surrounded by a protein coat. Some viruses have the ability to freely replicate in the environment. Viruses may be composed of RNA or DNA Viruses are neither prokaryotic nor eukaryotic.
Some viruses have the ability to freely replicate in the environment.
The CDC and OSHA recommend that all laboratory professionals follow: Infection Control Precautions Standard Precautions Universal Precautions Bloodborne Precautions
Standard Precautions
The Christie, Atkins, and Munch-Petersen (CAMP) test is based on enhanced hemolysis between CAMP factor and β-lysin from: Staphylococcus aureus Streptococcus agalactiae Staphylococcus epidermidis Enterococcus spp.
Staphylococcus aureus
A patient is admitted to the hospital for very severe back pain. He develops a fever one day after he his admitted and the physician orders a blood culture. The phlebotomist drew two sets of blood cultures. The next day, the MLS in the laboratory reported that one of the blood cultures was positive. The doctor suspects that the sample was likely contaminated as the patient's health has significantly improved. Which organism would you expect identify from the culture bottle? Stapylococcus aureus Staphylococcus epidermidis Staphylococcus saprophyticus Streptococcus pyogenes
Staphylococcus epidermidis
Which of the following Group A Streptococcus virulence factors is correctly described? Steptolysin O: Oxygen labile and antigenic Hyaluronidase: Causes lysis of fibrin clots and aids in the spread of infection Streptokinase: Enzyme that destroys connective tissue
Steptolysin O: Oxygen labile and antigenic
A control strain of Clostridium should be used in an anaerobe jar to assure: The plate media is working. That an anaerobic environmental is achieved. That the jar is filled with a sufficient number of plates. That the indicator strip is checked.
That an anaerobic environmental is achieved.
A bacterial organism is cultured in a medium containing a pH indicator. After 24 hours of growth, the medium has changed from red to yellow. What does the color change tell you about the identity of the organism? Answers: The organism is able to grow in high concentations of NaCL The organism is able to ferment a sugar that is present in the medium. The organism produces carbon dioxide The organism produces hydrogen sulfide.
The organism is able to ferment a sugar that is present in the medium.
The drug level required for the clinical treatment of the pathogen. Answers: Therapeutic Dose Therapeutic Index Toxic Dose Toxic Index
Therapeutic Dose
Establishing the pathogenicity of a microorganism isolated from a child's throat and identified as Corynebacterium diptheria would depend on: Answers: The morphological appearance as revealed on a Gram stain Hemolysis Toxigenecity Growth on Tinsdale tellurite agar
Toxigenecity
Which of the following precautions must be taken when handling bacterial cultures? (Select all that apply) Adhesive bandages or small finger cots should be worn directly over cuts or hangnails Plates should not be waved in front of the face to determine the odor of the organism Any plates growing a fungus should immediately be sealed, and the culture should be worked on in a biosafety cabinet. Splash guards are recommended for any procedure that may produce splashes, such as work at the blood culture bench.
all the above
Corynebacterium diphtheriae Treatment includes Early administration of _________-to control organism. Antibiotic therapy: penicillin or erythromycin
antitoxin
Which species of Mycobacterium includes a BCG strain used for vaccination against tuberculosis? Answers: tuberculosis bovis kansasii fortuitium/chelonae complex.
bovis
β-Hemolysis is complete __________of erythrocytes in SBA around or under the colonies because of the complete lysis of RBCs.
clearing