Microbiology Interview Preparation Guide
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Microbiology Interview Questions and Answers will guide us now that Microbiology is the study of microorganisms, which are unicellular or cell-cluster microscopic organisms. This includes eukaryotes such as fungi and protists, and prokaryotes. Viruses, though not strictly classed as living organisms, are also studied. So learn more about Microbiology with the help of this Microbiology Interview Questions with Answers guide

124 Microbiology Questions and Answers:

1 :: All Enterobacteriaceae share all of the following characteristics EXCEPT?

* A. Ferment glucose
* B. Reduce nitrates to nitrites
* C. Oxidase positive
* D. Gram negative
* E. Rod-shaped (bacilli)

Correct Answer: C

2 :: What is the O antigen of Enterobacteriaceae?

* A. Cell surface polysaccharide
* B. A channel controlling substance taken into the organism.
* C. A flagellar protein
* D. A peptidoglycan matrix important for cellular rigidity
* E. Cell wall lipopolysaccharide

Correct Answer: E

3 :: Which of the following statements about the 23-valent pneumococcal vaccine is not correct?

* A. It is a protein-conjugated, polysaccharide vaccine.
* B. It is poorly immunogenic in young children and immuno compromised hosts.
* C. It is routinely recommended for immune competent adults and children >2 yrs. of age at risk for serious pneumococcal disease.
* D. It protects against the major serotypes of pneumococci causing infection.
* E. An adult with asplenia would be a candidate for this vaccine.

Correct Answer: A

4 :: Which of the following statements about Group B a streptococcus (Streptococcus agalactiae) is not correct?

* A. They are important causes of toxic strep syndrome.
* B. They are frequent colonizers of the female genital tract.
* C. Screening for this pathogen during pregnancy has reduced the incidence of neonatal sepsis.
* D. These organisms are b-hemolytic.
* E. They are important causes of urinary tract infections and bacteremia in elderly and diabetic adults.

Correct Answer: A

6 :: All of the following statements about the M-protein of Group A- Streptococci are correct EXCEPT?

* A. The amino terminal portion (distal portion) is variable, accounting for over 80 distinct serotypes.
* B. M proteins allow streptococci to resist phagocytosis.
* C. Antibodies to M protein confer type-specific immunity.
* D. M protein is the major virulence factor of Group A streptococci
* E. M protein is the major constituent of the capsule of Group A streptococci

Correct Answer: E

7 :: Which of the following extracellular enzymes produced by Group A-streptococci is called “spreading factor”, an enzyme important in skin and soft tissue infection?

* A. Streptokinase
* B. Hyaluronidase
* C. M Protein
* D. Deoxyribonuclease C
* E. None of the above

Correct Answer: D

8 :: The diagnosis of septicemia should be considered in patients who are at increased risk of blood stream infection (often secondary to local disease, such as urinary tract infection or pneumonia). All of the following are factors predisposing patients to septicemia except?

* A. Underlying diseases that appear to compromise host defenses, such as diabetes, lymphoma, etc
* B. Patients with a polymorphonuclear leukocyte count less than 1000/mm3
* C. Patients with polymorphonuclear leukocyte counts of 10,000 to 20,000
* D. Long term therapy with broad-spectrum antimicrobials.

Correct Answer:

9 :: Physical findings and other factors that should suggest the presence of septicemia in a particular patient are all of the following except?

* A. Shaking chills, spiking fevers
* B. Conjunctivitis
* C. Nausea, vomiting, diarrhea
* D. in elderly patients, decreased urine output or mental changes (confusion)

Correct Answer: B

10 :: It is extremely difficult to eradicate staphylococcal infection in the presence of a foreign body. Thus, infected artificial joints and infected intravenous lines often must be removed in conjunction with optimal intravenous anti-staphylococcal therapy with oxacillin or nafcillin (sometimes in combination with rifampin) in order to eradicate such staphylococcal infections (and these attempts are not always successful). Staphylococcal infection of bone may persist for many years despite what should be optimal antimicrobial therapy. The most likely reason for this tenacity of staphylococcal osteomyelitis is:?

* A. The Staphylococcal pilus gene is up-regulated by oxacillin
* B. Fragments of dead bone, called "involucrum" may act as a foreign body, and may have to be removed for optimal eradication of the staphylococcal infection.
* C. Staphylococci may be perceived by the patient's immune system as a positive factor, because the staphylococci produce an extracellular enzyme, obtundokinase, which makes the patient more alert.
* D. Staphylococci are such an integral part of our normal flora that they are treated as "self" rather than "non-self", and no immune reaction to them occurs.

Correct Answer: B

12 :: Which of the following diseases are not transmitted by ticks?

* A. Ulceroglandular tularemia
* B. Bubonic plague
* C. Relapsing fever
* D. Lyme disease

Correct Answer: B

13 :: A 20 year old patient comes to the homeless clinic with a skin abscess on the right arm. A swab from the intact skin overlying this abscess grows coagulase negative staphylococci. An aspirate obtained sterilely with a needle and syringe grows Staphylococcus aureus. About these 2 organisms in this patient you can say?

* A. Both are normal flora and contaminated the specimens sent to the lab
* B. The staph aureus is a pathogen and the coagulase negative staph is not
* C. The coagulase negative staphylococcus is a pathogen
* D. The coagulase negative staphylococcus is an opportunistic pathogen

Correct Answer: B

16 :: Characteristics of a bacterial capsule include?

* A. All bacteria have one
* B. It is composed of peptidoglycan
* C. It is an important mechanism for protecting a bacteria against ingestion by PMNs
* D. It is what causes the gram stain reaction

Correct Answer: C

17 :: As a budding basic scientist you work in a research laboratory and discover a chemical that removes the cell wall from bacteria but leaves the organism undamaged otherwise. Things that the bacteria will lose because of this include?

* A. The ability to stain gram positive: all will look gram negative
* B. The ability to move
* C. The ability to have a gram stain result
* D. The ability to attach to other cells

Correct Answer: C

18 :: Under the electron microscope you keep at home next to your MP3 player you look at a single bacterium living in your mouth. You see a single polar flagellum stretching off from one end looking very much like a tail. A characteristic of this organism should be?

* A. An ability to stay in one place for a very long time
* B. An ability to move in the direction opposite the flagellum
* C. An ability to avoid ingestion by PMNs
* D. An ability to induce a large antibody response

Correct Answer: B

19 :: On the same day the clinical laboratory identifies two strains of the same bacterial species. One of these strains has pili on the surface; the other does not. In terms of the clinical status of the two patients it is likely that?

* A. Patient with the piliated strain is ill, the other patient is not
* B. Patient with the piliated strain is not ill, the other patient is
* C. Both patients are ill since pili do not correlate with virulence
* D. Patient with the piliated strain is a child, the other patient is an adult

Correct Answer: A

20 :: Infections caused by anaerobes are?

* A. Usually confined to the abdomen
* B. Never seen in the lung because of its excellent blood supply
* C. Mixed
* D. Rapidly progressive

Correct Answer: C