BACTE PRE-TEST

Mannitol salt agar is selective and differential for which group of organism?(1 Point) A. Staphylococcus spp. B. Enterococcus spp. C. Gram positive cocci D. Streptococcus spp.

A. Staphylococcus spp.

Most pathogenic bacteria are characterized as: (1 Point) A. Psychrophilic B. Mesophilic C. Thermophilic D. Thermoduric

B. Mesophilic

An organism that is ONPG positive possesses:(1 Point) A. Beta-galactosidase and lactose permease B. Only Beta-galactosidase C. Only lactose permease D. Cytochrome oxidase

B. Only Beta-galactosidase

The colonies shown in the blood (BAP) agar (upper) and MacConkey (MAC) agar (lower) biplate are a 24 hour growth from an aerobic blood culture bottle that became positive at 12 hours after inoculation. The appearance of the colonies on MAC agar rules out the following bacterial species: (1 Point) A. Escherichia coli B. Klebsiella pneumoniae C. Pseudomonas aerugiosa D. Enterobacter aerogenes

C. Pseudomonas aeruginosa

Cultures from a post-abdominal cellulitis specimen grew Gram-negative pleomorphic rods with the following characteristics: Grows on KV agar but does not show fluorescence Produces black colonies BBE agar Resistant to penicillin Which of the following is the MOST likely identification?(1 Point) A. Bacteroides fragilis B. Fusobacterium nucleatum C. Prevotella species D. Veillonella species

A. Bacteroides fragilis

Burkholderia mallei is the causative agent of:(1 Point) A. Glander's B. Melidiosis C. Neontal sepsis D. Onion bulb rot

A. Glander's

Two methods which may be used to determine motility are:(1 Point) A. Hanging drop and motility medium B. Hanging drop and gram stain C. Motility medium and simple stain D. Gram stain and motility medium

A. Hanging drop andmotility medium

Which of the following is not classified as a direct route of infection? (1 Point) A. Ingestion of contaminated food or water B. Sexual contact C. Hand to Hand contact D. Congenital transmission

A. Ingestion of contaminated food or waterB

Which of the terms of the normal growth cycle best describes a stage when bacteria are adapting to a new environment?(1 Point) A. Lag phase B. Log phase C. Stationary D. Decline

A. Lag phase

Which reaction is incorrect for Pseudomonas aeruginosa?(1 Point) A. Pyocyanin production B. Pyoverdin production C. Alkalizes acidamine D. Fails to grow at 42C

A. Pyocyanin production

The plasma of choice for coagulase test is derived from:(1 Point) A. Rabbit B. Sheep C. Human D. Horse

A. Rabbit

Spores are found in selected groups of bacteria. Which of the following statements best describes the major advantage to the bacteria that possess these structures?(1 Point) A. Spores are resistant to heat, cold, drying, more chemicals and boiling B. Spores allow an organism to better control in local environment C. Spores allow bacteria to attach or adhere to host tissue D. Organisms with spores have a more efficient exchange of genetic material

A. Spores are resistant to heat,cold, drying,more chemicals and boiling

The red ring at the top of the media in this tube indicates a positive indole reaction. The precursor substance in the medium from which the indole is produced is: (1 Point) A. Tryptophan B. p-dimethylaminobenzaldehyde C. Pyruvic acid D. Peptone

A. Tryptophan

The selective medium thiosulfate citrate bile salts sucrose agar is especially formulated for isolating which pathogen from stool cultures?(1 Point) A. Vibrio B. Salmonella C. Shigella D. Plesiomonas

A. Vibrio

Which of the following is the most likely identification of an acid fast bacilli recovered from an induced sputum with these culture findings? Slow growth at 37o C; Niacin test = negative; Pigmented photochromogenic; Nitrate test = positive; Catalase = positive(1 Point) A. Mycobacterium kansasii B. Mycobacterium tuberculosis C. Mycobacterium similae D. Mycobacterium chelonei

A.Mycobacterim kansasii

Which of the following is/are general characteristic/s of Staphylococci 1. Catalase positive 2. Motile, non-spore forming 3. Aerobic, facultative anaerobe 4. Gram negative cocci in pairs or clusters(1 Point) A. 1 and 2 B. 1 and 3 C. 2 and 4 D. 3 and 4

B. 1 and 3

When an unknown member of the Enterobacteriaceae family is recovered in primary culture, which key characteristics would lead you to suspect Klebsiella pneumoniae?(1 Point) A. Indole production B. Absence of motility C. Positive ornithine decarboxylase D. Positive phenylalanine deaminase

B. Absence of motility

85% N2, 10% H2, , 5% CO2 is the environmental condition?(1 Point) A. Aerobes B. Anaerobes C. Capnophiles D. Microaerophiles

B. Anaerobes

Antimicrobial agents that kill the microbe, leading to cell lysis are categorized as:(1 Point) A. Bacteriostatic B. Bactericidal C. Narrow-spectrum antibiotics D. Super antibiotics

B. Bactericidal

Complete hemolysis of blood is known as:(1 Point) A. Alpha-hemolysis B. Beta-hemolysis C. Gamma-hemolysis D. Synergistic hemolysis

B. Beta-hemolysis

The Frei antigen test is used as an aid in the diagnosis of:(1 Point) A. Streptococcus pneumoniae B. Chlamydia trachomatis C. Streptococcus pyogenes D. Bacillus anthracis

B. Chlamydia trachomatis

What organism is responsible for a potentially lethal type of food poisoning caused by improperly canned food?(1 Point) A. Bacillus cereus B. Clostridium botulinum C. Clostridium perfringens D. Staphylococcus aureus

B. Clostridium botulinum

Which one of the following organisms is commonly cultured from the nasopharynx of healthy people but is RARELY pathogenic?(1 Point) A. Beta hemolytic streptococci B. Corynebacterium spp C. Haemophilus influenzae D. Neisseria meningitidis

B. Corynebacterium spp

The mordant used in Ziehl-Neelsen staining technique is: (1 Point) A. Gram's iodine B. Heat C. Acid-alcohol D. Tergitol

B. Heat

Which of the following antigenic structure is considered the major virulence factor in the pathogenesis of Neisseria meningitidis?(1 Point) A. Pili B. Polysaccharide capsule C. Porin D. Opa protein

B. Polysaccharide capsule

The Weil-Felix test which serologically helpful for identification of Rickettsial infection uses:(1 Point) A. Proteus mirabilis strain OX-19 B. Proteus vulgaris strain OX-19 C. Antibody to a variety of Rickettsial infection D. A cross-reaction with Mycoplasma isolates

B. Proteus vulgaris strain OX-19

Which of the following is a non-fermenter?(1 Point) A. Escherichia coli B. Pseudomonas aeruginosa C. Yersinia enterocolitica D. Serratia marcescens

B. Pseudomonas aeruginosa

A throat swab is submitted for anaerobic culture. This specimen must be:(1 Point) A. Set up immediately B. Rejected C. Inoculated into thioglycolate broth D. Sent to a reference lab

B. Rejected

In preparing blood agar plates for determining hemolytic patters of streptococci, what is the first choice of whole blood?(1 Point) A. Horse B. Sheep C. Rabbit D. Human

B. Sheep

A blood culture yielded an organism with the following reactions: TSIA: K/A, gas (+), H2S (+); Citrate: Positive; Indole: Negative; Lysine: Positive; Ornithine: Positive; Motility: Positive; Phenylalanine: Negative; ONPG: Negative; Urease: Negative. What is the most likely identification of this organism?(1 Point) A. Citrobacter B. Proteus C. Salmonella D. Enterobacter

C. Salmonella

All Neisseria species are positive for the enzyme:(1 Point) A. Coagulase B. DNase C. Oxidase D. Penicillinase

C. Oxidase

All of the following are disease associated with Group A streptococcus except: (1 Point) A. Scarlet fever B. Septic Sore Throat C. Scalded Skin Syndrome D. Rheumatic Fever

C. Scalded Skin Syndrome

The culture of which sample routinely uses quantitation or counting of bacterial cells present to assist in the interpretation?(1 Point) A. Blood B. Sputum C. Urine D. Abscess

C. Urine

The production of acetelymethylcarbinol from dextrose constitutes the basis for which of the following tests?(1 Point) A. Neufeld-Quellung B. Cholera red C. Voges-Proskauer D. Oxidase

C. Vogues-Proskauer

A recto-sigmoidoscopy revealed pseudomembranes in a patient with severe diarrhea following prolonged treatment with ampicillin. Which of the following organisms is MOST likely to be isolated?(1 Point) A. Bacteroides fragilis B. Clostridium botulinum C. Clostridium difficile D. Fusobacterium nucleatum

C. Clostridium difficile

The tendency for the cells of Mycobacterium tuberculosis to assemble in linear aggregates as seen in this image of an acid-fast stained preparation is caused by production of:(1 Point) A. Lysozyme B. Niacin C. Cording factor D. Oleic acid

C. Cording factor

The catalase test is useful for:(1 Point) A. Identification of E.coli from other Enterobacteriaceae B. Selection of Beta-hemolytic streptococcus C. Differentiation of Staphylococcus from Streptococcus D. Comparison of Staphylococcus and Micrococcus

C. Differentiation of Staphylococcus from Streptococcus

Illustrated in this photograph are colonies growing on the surface of a chocolate agar plate. The colonies were recovered from a subcutaneous infection of the forearm and had a bleach odor. The most likely identification is: (1 Point) A. Moraxella lacunata B. Haemophilus aphrophilus C. Eikenella corrodens D. Capnocytophaga canimorsus

C. Eikenella corrodens

A unidentified colony was inoculated to the surface of a filter paper strip impregnated with cytochrome oxidase reagent (dimethyl-p-phenylenediamine dihydrochloride) as shown in the picture on the right. The family of bacteria ruled out by the reaction seen is: (1 Point) A. Pasteurellaceae B. Neisseriaceae C. Enterobacteriaceae D. Pseudomonadaceae

C. Enterobactericeae

A mordant that is applied after the primary stain to chemically bond the alkaline dye to the bacterial cell wall is which of the following?(1 Point) A. Safranin B. Crystal violet C. Gram's iodine D. Acetone Alcohol

C. Gram's iodine

Which of the following characteristics uniquely describes genus Mycoplasma? (1 Point) A. Does not contain RNA B. Lacks cell membrane C. Lacks a cell wall D. Requires living cells for growth

C. Lacks cell wall

This organism commonly causes abortion and is recovered from still-born fetus:(1 Point) A. Bacteroides fragilis B. Campylobacter spp C. Listeria monocytogenes D. Streptococcus pyogenes

C. Listeria monocytogenes

The best specimen for isolation of Bordetella pertussis is which of the following?(1 Point) A. Throat swab B. Sputum C. Nasopharyngeal aspirates D. Anterior nose swabs

C. Nasopharyngeal aspirates

Which of the following organisms typically produces star-shaped colonies?(1 Point) A. Streptococcus pneumoniae B. Staphylococcus aureus C. Proteus mirabilis D. Aggregatibacter actinomycetemcomitans

D. Aggregatibacter actinomycetemcomitans

From the choices listed below, which organism is classified as an obligate anaerobe?(1 Point) A. Mycobacteria B. Staphylococcus aureus C. Neisseria spp D. Clostrium noyvi

D. Clostridium noyvi

Which of the following specimens would be best for identifying Bacillus cereus as the cause of an outbreak of food poisoning? (1 Point) A. Blood B. Rectal Swab C. Stool samples D. Food

D. Food

Which of the following organismshows a presumptive identification whcih can be made wheen vaginal discharge shows clue cells? A. Bacillus cereus B. Neisseria gonorrhoeae C. Escherichia coli D. Gardnerella vaginalis

D. Gardnerella vaginalis

Darkfield microscopy is most often used to study:(1 Point) A. Candida albicans B. Mycobacterium tuberculosis C. Parasitic nuclei D. Hard chancre

D. Hard chancre

The "fried egg-like" growth - colonies with dense centers surrounded by a less dense periphery - seen here on PPLO agar is most likely caused by: (1 Point) A. Streptococcus pneumoniae B. Klebsiella pneumoniae C. Mycobacterium sp. D. Mycoplasma sp.

D. Mycoplasma sp.

The term that best describes the location of the flagella which entirely surrounds the bacteria is:(1 Point) A. Atrichous B. Monotrichous C. Amphitrichous D. Peritrichous

D. Peritrichous