Mock Test for Microbiologist Certification ( Specialization )

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Lab Test Academy

NHPC , Micro Specialization

M.Sc Medical Microbiology

Welcome to Our Mock Test for M.Sc Medical Microbiology ! 🚀 A warm welcome to Lab Test Academy ! We're thrilled to guide you through this M.Sc Medical Microbiology Mock Test experience.

1 / 100

Category: NHPC , Micro Specialization

1. The "trophozoite" stage of Entamoeba histolytica is primarily found in :

a) Cyst wall

b) Human feces during acute amoebiasis

c) Mosquito vector

d) Contaminated water

2 / 100

Category: NHPC , Micro Specialization

2. All of the following are appropriate when attempting to isolate N. gonorrhoeae from a genital specimen except:

a) Transport the genital swab in charcoal transport medium

b) Plate the specimen on modified Thayer–Martin (MTM) medium

c) Plate the specimen on New York City or Martin–Lewis agar

d) Culture specimens in ambient oxygen at 37°C

3 / 100

Category: NHPC , BMLT

3. Which bacterium is oxidase-positive ?

a) Escherichia coli

b) Klebsiella pneumoniae

c) Pseudomonas aeruginosa

d) Salmonella enterica

4 / 100

Category: NHPC , Micro Specialization

4. Which of the following reagents is added to detect the production of indole?

a) p-Dimethylaminobenzaldehyde

b) Bromcresol purple

c) Methyl red

d) Methyl red

5 / 100

Category: NHPC , Micro Specialization

5. Which parasite causes "Chagas disease" ?

a) Leishmania donovani

b) Trypanosoma brucei

c) Trypanosoma cruzi

d) Plasmodium falciparum

6 / 100

Category: NHPC , Micro Specialization

6. Xylose lysine deoxycholate (XLD) agar is a highly selective medium used for the recovery of which bacteria?

a) Staphylococcus spp. from normal flora

b) Yersinia spp. that do not grow on Hektoen agar

c) Enterobacteriaceae from gastrointestinal specimens

d) Streptococcus spp. from stool cultures

7 / 100

Category: NHPC , Micro Specialization

7. A specimen for Enterobius vermicularis diagnosis requires :

a) Diarrheal stool examined within 30 minutes

b) Perianal swab instead of stool

c) Urine preserved at 4°C

d) Blood collected in EDTA tubes

8 / 100

Category: NHPC , Micro Specialization

8. Which biosafety level (BSL) is required for Mycobacterium tuberculosis cultures ?

a) BSL-1

b) BSL-2

c) BSL-3

d) BSL-4

9 / 100

Category: NHPC , Micro Specialization

9. Capsules contribute to bacterial pathogenicity by :

a) Facilitating binary fission

b) Synthesizing respiratory enzymes

c) Inhibiting phagocytosis

d) Promoting spore formation

10 / 100

Category: NHPC , Micro Specialization

10. The bacterial cell wall is primarily composed of :

a) Cellulose and chitin

b) Phospholipids and cholesterol

c) Mucopeptide (peptidoglycan) with N-acetylglucosamine and N-acetylmuramic acid

d) Lipopolysaccharides and teichoic acid

11 / 100

Category: NHPC , Micro Specialization

11. Which bacterium has an exceptionally long generation time of approximately 20 days ?

a) Escherichia coli

b) Mycobacterium tuberculosis

c) Staphylococcus aureus

d) Mycobacterium leprae

12 / 100

Category: NHPC , Micro Specialization

12. What does the "E" in ESKAPE pathogens represent ?

a) Escherichia coli

b) Enterococcus faecium

c) Enterobacter species

d) Extended-spectrum β-lactamases

13 / 100

Category: NHPC , Micro Specialization

13. Select the method of choice for recovery of anaerobic bacteria from a deep abscess.

a) Cotton fiber swab of the abscess area

b) Skin snip of the surface tissue

c) Needle aspirate after surface decontamination

d) Swab of the scalpel used for débridement

14 / 100

Category: NHPC , Micro Specialization

14. A Pseudomonas aeruginosa isolate resistant to imipenem likely possesses :

a) VanA gene

b) KPC carbapenemase

c) Efflux pumps or metallo-β-lactamases

d) ESBL TEM-type

15 / 100

Category: NHPC , Micro Specialization

15. Which factor is critical during the pre-analytical phase ?

a) Calibration of spectrophotometers

b) Proper specimen labeling and clinical details

c) Use of Levey-Jennings charts

d) Gram stain verification

16 / 100

Category: NHPC , Micro Specialization

16. What disease the Nesser will produce ?

a) Mumps

b) Rubella

c) Polio

d) Measles

17 / 100

Category: NHPC , Micro Specialization

17. Fimbriae (pili) are involved in :

a) DNA transfer during conjugation

b) Flagellar assembly

c) Endospore germination

d) Capsule formation

18 / 100

Category: NHPC , Micro Specialization

18. The Voges-Proskauer test detects production of :

a) Indole

b) Hydrogen sulfide

c) Acetyl methyl carbinol (acetoin)

d) Phenylpyruvic acid

19 / 100

Category: NHPC , Micro Specialization

19. Which immunodeficiency is X-linked and affects B-cell maturation ?

a) DiGeorge syndrome

b) Bruton's agammaglobulinemia

c) SCID

d) Chediak-Higashi syndrome

20 / 100

Category: NHPC , Micro Specialization

20. What is the primary mechanism of action of halogens like iodine ?

a) Disruption of cell membranes

b) Denaturation of proteins and oxidation of amino acids

c) Inhibition of DNA replication

d) Coagulation of nucleic acids

21 / 100

Category: NHPC , Micro Specialization

21. Plasmids confer survival advantages by encoding :

a) Ribosomal RNA

b) Peptidoglycan subunits

c) Toxigenicity and antibiotic resistance

d) Capsular polysaccharides

22 / 100

Category: NHPC , Micro Specialization

22. At which pH does the methyl red (MR) test become positive?

a) 7.0

b) 6.5

c) 6.0

d) 4.5

23 / 100

Category: NHPC , Micro Specialization

23. A positive indole test identifies bacteria that can :

a) Utilize citrate as carbon source

b) Decompose tryptophan to indole

c) Reduce nitrate to nitrite

d) Produce hydrogen sulfide

24 / 100

Category: NHPC , Micro Specialization

24. Pleomorphism is most commonly associated with :

a) Bacillus anthracis

b) Mycoplasma species

c) Escherichia coli

d) Streptococcus pyogenes

25 / 100

Category: NHPC , Micro Specialization

25. What is the process by which most bacteria reproduce ?

a) Budding

b) Sporulation

c) Binary fission

d) Fragmentation

26 / 100

Category: NHPC , Micro Specialization

26. Select the primary and differential media of choice for recovery of most fecal pathogens.

a) MacConkey, blood, birdseed, and Campylobacter (Campy) agars

b) Hektoen, MacConkey, Campy, colistin–nalidixic acid (CNA) agars

c) CNA and Christensen urea agars and thioglycollate media

d) Blood, Campy, Mueller–Hinton agars, and thioglycollate media

27 / 100

Category: NHPC , Micro Specialization

27. Which component is essential for Internal Quality Control (IQC) ?

a) Inter-laboratory comparison

b) Retrospective assessment by external agencies

c) Continuous monitoring of daily procedures

d) Financial auditing of laboratory expenses

28 / 100

Category: NHPC , Micro Specialization

28. Toxic shock syndrome is attributed to infection with:

a) Staphylococcus epidermidis

b) Staphylococcus hominis

c) Staphylococcus aureus

d) Staphylococcus saprophyticus

29 / 100

Category: NHPC , Micro Specialization

29. Which organism gives a positive citrate utilization test ?

a) Escherichia coli

b) Shigella dysenteriae

c) Klebsiella pneumoniae

d) Streptococcus pyogenes

30 / 100

Category: NHPC , Micro Specialization

30. A laboratory uses Staphylococcus aureus ATCC 25923 for AST QC. What parameter does this control validate ?

a) Catalase reagent stability

b) Mueller Hinton Agar performance

c) Gram stain accuracy

d) Centrifuge calibration

31 / 100

Category: NHPC , Micro Specialization

31. The bacterial cytoplasmic membrane lacks :

a) Lipoproteins

b) Permease enzymes

c) Cholesterol

d) Respiratory pigments

32 / 100

Category: NHPC , Micro Specialization

32. Which bacterium is nitrate reduction test positive ?

a) Haemophilus ducreyi

b) Pseudomonas aeruginosa

c) Members of Enterobacteriaceae

d) Streptococcus pyogenes

33 / 100

Category: NHPC , Micro Specialization

33. Specimens for virus culture should be transported in media containing:

a) Antibiotics and 5% sheep blood

b) Saline and 5% sheep blood

c) 22% bovine albumin

d) Antibiotics and nutrient

34 / 100

Category: NHPC , Micro Specialization

34. Which method counts BOTH live and dead bacterial cells in a sample ?

a) Viable Count

b) Total Count

c) Dilution Method

d) Planting Method

35 / 100

Category: NHPC , Micro Specialization

35. The "string test" is specific for :

a) Vibrio cholerae

b) Haemophilus influenzae

c) Klebsiella pneumoniae

d) Pseudomonas aeruginosa

36 / 100

Category: NHPC , Micro Specialization

36. Cerebrospinal fluid (CSF) should be cultured immediately, but if delayed the specimen should be:

a) Refrigerated at 4°C to 6°C

b) Frozen at –20°C

c) Stored at room temperature for no longer than 24 hours

d) Incubated at 37°C and cultured as soon as possible

37 / 100

Category: NHPC , Micro Specialization

37. Which method is used for long-term preservation of bacteria by drying ?

a) Pasteurization

b) Autoclaving

c) Freeze drying (Lyophilization)

d) Filtration

38 / 100

Category: NHPC , Micro Specialization

38. The basal body of flagella is responsible for :

a) Filament assembly

b) Anchoring to the cell membrane

c) Adhesion to surfaces

d) Toxin production

39 / 100

Category: NHPC , Micro Specialization

39. A positive methyl red test indicates :

a) Production of acetoin

b) Maintenance of pH above 6.0

c) Glucose fermentation with pH <4.5

d) Citrate utilization

40 / 100

Category: NHPC , Micro Specialization

40. According to the Kirby–Bauer standard antimicrobial susceptibility testing method, what should be done when interpreting the zone size of a motile, swarming organism such as a Proteus species?

a) The swarming area should be ignored

b) The results of the disk diffusion method are invalid

c) The swarming area should be measured as the growth boundary

d) The isolate should be retested after diluting to a 0.05 McFarland standard

41 / 100

Category: NHPC , Micro Specialization

41. What phenomenon is frequently observed in the Decline Phase ?

a) Spore formation

b) Involution forms

c) Secondary metabolite production

d) Exponential growth

42 / 100

Category: NHPC , Micro Specialization

42. Alcohols like ethanol and isopropyl alcohol are most effective at which concentration?

a) 10-20%

b) 30-50%

c) 70-80%

d) 90-100%

43 / 100

Category: NHPC , Micro Specialization

43. Select the media of choice for recovery of Vibrio cholerae from a stool specimen.

a) MacConkey agar and thioglycollate media

b) Thiosulfate–citrate–bile–sucrose (TCBS) agar and alkaline peptone water (APW) broth

c) Blood agar and selenite-F (SEL) broth

d) CNA agar

44 / 100

Category: NHPC , Micro Specialization

44. Mueller Hinton Agar for antibiotic testing requires a thickness of :

a) 1mm

b) 2mm

c) 4mm

d) 10mm

45 / 100

Category: NHPC

45. Deoxycholate agar (DCA) is useful for the isolation of :

a) Enterobacteriaceae

b) Enterococcus spp.

c) Staphylococcus spp.

d) Neisseria spp.

46 / 100

Category: NHPC , Micro Specialization

46. In the test for urease production, ammonia reacts to form which product?

a) Ammonium citrate

b) Ammonium carbonate

c) Ammonium oxalate

d) Ammonium nitrate

47 / 100

Category: NHPC , Micro Specialization

47. The Quellung reaction is used to demonstrate :

a) Flagellar antigens

b) Capsules of Pneumococcus

c) Spore viability

d) Cell wall synthesis

48 / 100

Category: NHPC , Micro Specialization

48. The test used most often to separate the Micrococcaceae family from the Streptococcaceae family is:

a) Bacitracin

b) Catalase

c) Hemolysis pattern

d) All of these options

49 / 100

Category: NHPC , Micro Specialization

49. A positive phenylalanine deaminase test is characteristic of :

a) Escherichia coli

b) Proteus species

c) Staphylococcus aureus

d) Pseudomonas aeruginosa

50 / 100

Category: NHPC , Micro Specialization

50. The ortho-nitrophenyl-β-galactopyranoside (ONPG) test is most useful when differentiating:

a) Salmonella spp. from Pseudomonas spp.

b) Shigella spp. from some strains of Escherichia coli

c) Klebsiella spp. from Enterobacter spp.

d) Proteus vulgaris from Salmonella spp.

51 / 100

Category: NHPC , Micro Specialization

51. The Voges–Proskauer (VP) test detects which end product of glucose fermentation?

a) Acetoin

b) Nitrite

c) Acetic acid

d) Hydrogen sulfide

52 / 100

Category: NHPC , Micro Specialization

52. A sheep blood agar plate is used as a primary isolation medium when all of the following organisms are to be recovered from a wound specimen except:

a) β-Hemolytic streptococci and coagulase-positive staphylococci

b) Haemophilus influenzae and Haemophilus parainfluenzae

c) Proteus spp. and Escherichia coli

d) Pseudomonas spp. and Acinetobacter spp.

53 / 100

Category: NHPC , Micro Specialization

53. For ESBL-producing bacteria, which antibiotic class should ALWAYS be reported as resistant ?

a) Carbapenems

b) Cephamycins (e.g., cefoxitin)

c) Third-generation cephalosporins

d) Fluoroquinolones

54 / 100

Category: NHPC , Micro Specialization

54. Which phase of the bacterial growth curve is characterized by a constant viable count ?

a) Lag Phase

b) Log Phase

c) Stationary Phase

d) Decline Phase

55 / 100

Category: NHPC , Micro Specialization

55. Which test detects Treponema pallidum non-specifically ?

a) ELISA

b) FTA-ABS

c) VDRL

d) Western blot

56 / 100

Category: NHPC , Micro Specialization

56. The aseptic collection of blood cultures requires that the skin be cleansed with:

a) 2% iodine and then 70% alcohol solution

b) 70% alcohol and then 2% iodine or an iodophor

c) 70% alcohol and then 95% alcohol

d) 95% alcohol only

57 / 100

Category: NHPC , Micro Specialization

57. Which class of antibiotics is used for the treatment of serious gram-negative infections as well as infections with Mycobacterium tuberculosis?

a) Cephalosporins

b) Penicillins

c) Tetracyclines

d) Aminoglycosides

58 / 100

Category: NHPC , Micro Specialization

58. Which characteristic is NOT used to describe colony morphology on solid media ?

a) Hemolysis pattern

b) Elevation (e.g., umbonate)

c) Catalase production

d) Edge appearance (e.g., crenated)

59 / 100

Category: NHPC , Micro Specialization

59. Bacteria that require oxygen for growth and can ONLY grow in its presence are called :

a) Facultative Anaerobes

b) Obligate Aerobes

c) Microaerophiles

d) Obligate Anaerobes

60 / 100

Category: NHPC , Micro Specialization

60. Which antibiotic inhibits bacterial cell wall synthesis ?

a) Erythromycin

b) Penicillin

c) Tetracycline

d) Ciprofloxacin

61 / 100

Category: NHPC , Micro Specialization

61. Which of the following variables may change the results of an MIC?

a) Inoculum size

b) Incubation time

c) Growth rate of the bacteria

d) All of these options

62 / 100

Category: NHPC , Micro Specialization

62. What is the term for the time required for one bacterium to divide into two daughter cells ?

a) Replication Time

b) Division Interval

c) Generation Time

d) Exponential Period

63 / 100

Category: NHPC , Micro Specialization

63. Beta-lactamase production confers resistance to :

a) Aminoglycosides

b) Macrolides

c) Penicillins

d) Tetracyclines

64 / 100

Category: NHPC , Micro Specialization

64. What is the primary purpose of Quality Assurance (QA) in a clinical microbiology laboratory ?

a) To perform daily equipment calibration

b) To ensure final reported results are correct

c) To reduce healthcare costs by eliminating tests

d) To train physicians in specimen collection

65 / 100

Category: NHPC

65. Chocolate agar and modified Thayer–Martin agar are used for the recovery of:

a) Haemophilus spp. and Neisseria spp., respectively

b) Haemophilus spp. and N. gonorrhoeae, respectively

c) Neisseria spp. and Streptococcus spp., respectively

d) Streptococcus spp. and Staphylococcus spp., respectively

66 / 100

Category: NHPC , Micro Specialization

66. Prereduced and vitamin K1 -supplemented blood agar plates are recommended isolation media for:

a) Mycobacterium marinum and Mycobacterium avium intracellulare

b) Bacteroides, Peptostreptococcus, and Clostridium spp

c) Proteus spp.

d) Enterococcus spp.

67 / 100

Category: NHPC , Micro Specialization

67. For antimicrobial susceptibility testing (AST) QC, Escherichia coli ATCC 25922 is used as a :

a) Gram stain control

b) Reference strain for disc diffusion

c) Catalase test positive control

d) Anaerobic culture indicator

68 / 100

Category: NHPC , Micro Specialization

68. Kligler iron agar (KIA) differs from triple-sugar iron agar (TSI) in the:

a) Kligler iron agar (KIA) differs from triple-sugar iron agar (TSI) in the:

b) Ability to detect H2 S production

c) Use of sucrose in the medium

d) Color reaction denoting production of acid

69 / 100

Category: NHPC , Micro Specialization

69. Endospores are produced by bacteria to :

a) Facilitate conjugation

b) Survive unfavorable conditions

c) Enhance motility

d) Synthesize toxins

70 / 100

Category: NHPC , Micro Specialization

70. A Klebsiella pneumoniae isolate tests positive for the Modified Hodge Test. This confirms :

a) ESBL production

b) Vancomycin resistance

c) Carbapenemase (KPC) activity

d) AmpC β-lactamase expression

71 / 100

Category: NHPC , Micro Specialization

71. Colistin–nalidixic acid agar (CNA) is used primarily for the recovery of:

a) Neisseria species

b) Enterobacteriaceae

c) Pseudomonas aeruginosa

d) Staphylococcus aureus

72 / 100

Category: NHPC , Micro Specialization

72. Which type of bacteria grows best in the presence of increased carbon dioxide tension (5-10%) ?

a) Mesophiles

b) Acidophiles

c) Capnophils

d) Microaerophiles

73 / 100

Category: NHPC , Micro Specialization

73. In which phase does bacterial cell division occur at its maximum rate ?

a) Lag Phase

b) Log Phase

c) Stationary Phase

d) Decline Phase

74 / 100

Category: NHPC , Micro Specialization

74. The "eggshell" appearance in stool microscopy is characteristic of :

a) Ascaris lumbricoides

b) Enterobius vermicularis

c) Trichuris trichiura

d) Taenia solium

75 / 100

Category: NHPC , Micro Specialization

75. In the Kirby-Bauer method, antibiotic disks are typically made from :

a) Gelatin sheets

b) Cellulose acetate

c) Whatman No. 1 filter paper

d) Silica gel

76 / 100

Category: NHPC , Micro Specialization

76. The majority of Haemophilus influenzae infections are caused by which of the following capsular serotypes?

a) a

b) b

c) c

d) d

77 / 100

Category: NHPC , Micro Specialization

77. Which component is responsible for bacterial motility ?

a) Fimbriae

b) Capsule

c) Flagella

d) Pili

78 / 100

Category: NHPC , Micro Specialization

78. Which of the following tests is used routinely to identify Staphylococcus aureus?

a) Slide coagulase test

b) Tube coagulase test

c) Latex agglutination

d) All of these options

79 / 100

Category: NHPC , Micro Specialization

79. At which pH does the methyl red (MR) test become positive?

a) Blue color in the medium after 24 hours of incubation at 35°C

b) Red color in the medium after 18 hours of incubation at 35°C

c) Yellow color in the medium after 24 hours of incubation at 35°C

d) Green color in the medium after 18 hours of incubation at 35°C

80 / 100

Category: NHPC , Micro Specialization

80. Protoplasts and spheroplasts are characterized by :

a) Retention of the original bacterial shape

b) Resistance to lysozyme

c) Spherical morphology regardless of original shape

d) Presence of intact cell walls

81 / 100

Category: NHPC , Micro Specialization

81. The HACEK group of organisms (Haemophilus aphrophilus, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella spp.) are all known for which type of infection?

a) Urinary tract

b) Endocarditis

c) Pharyngitis

d) Tonsillitis

82 / 100

Category: NHPC , Micro Specialization

82. Which single test best separates Klebsiella oxytoca from K. pneumoniae?

a) Urease

b) Sucrose

c) Citrate

d) Indole

83 / 100

Category: NHPC , Micro Specialization

83. The breakpoint of an antimicrobial drug refers to :

a) The amount needed to cause bacteriostasis

b) A minimum inhibitory concentration (MIC) of 16 μg/mL or greater

c) A MIC of 64 μg/mL or greater

d) The level of drug that is achievable in serum

84 / 100

Category: NHPC , Micro Specialization

84. The quellung test is used to identify which Streptococcus species?

a) S. pyogenes

b) S. agalactiae

c) S. sanguis

d) S. pneumoniae

85 / 100

Category: NHPC , Micro Specialization

85. Lactobacilli are examples of bacteria that prefer which pH range ?

a) Acidic pH (~3.0)

b) Neutral pH (7.2-7.4)

c) Alkaline pH (~10.5)

d) Any pH

86 / 100

Category: NHPC , Micro Specialization

86. Aspergillus fumigatus is identified by :

a) Unbranched hyphae

b) Septate hyphae with 45° angle branching

c) Spaghetti-and-meatball appearance

d) Broad, ribbon-like hyphae

87 / 100

Category: NHPC , Micro Specialization

87. Which Staphylococcus species, in addition to S. aureus, also produces coagulase?

a) S. intermedius

b) S. saprophyticus

c) S. hominis

d) All of these options

88 / 100

Category: NHPC , Micro Specialization

88. Hydrogen sulfide production in TSI agar is indicated by :

a) Pink color change

b) Gas bubbles in medium

c) Black precipitate

d) Zone of hemolysis

89 / 100

Category: NHPC , Micro Specialization

89. Which of the following is the correct definition of disinfection ?

a) The complete destruction of all microorganisms, including spores.

b) The removal or destruction of pathogenic organisms capable of causing infection.

c) The inhibition of bacterial growth in living tissues.

d) The use of heat to kill microorganisms.

90 / 100

Category: NHPC , Micro Specialization

90. Which virus causes syncytia formation in cell culture ?

a) Influenza virus

b) Respiratory syncytial virus (RSV)

c) Adenovirus

d) Rotavirus

91 / 100

Category: NHPC , Micro Specialization

91. When cleansing the skin with alcohol and then iodine for the collection of a blood culture, the
iodine (or iodophor) should remain intact on the skin for at least:

a) 10 sec

b) 30 sec

c) 60 sec

d) 5 min

92 / 100

Category: NHPC , Micro Specialization

92. Which vaccine uses live attenuated pathogens ?

a) Hepatitis B

b) Tetanus toxoid

c) MMR (measles, mumps, rubella)

d) Inactivated polio vaccine (IPV)

93 / 100

Category: NHPC , Micro Specialization

93. The Quellung reaction is used for capsular typing of :

a) Streptococcus pneumoniae

b) Neisseria meningitidis

c) Haemophilus influenzae

d) Cryptococcus neoformans

94 / 100

Category: Gram Stain

94. What happens during the decolorization step in Gram staining?

a) Gram-positive bacteria lose the crystal violet stain

b) Gram-negative bacteria lose the crystal violet stain

c) Both Gram-positive and Gram-negative bacteria retain the stain

d) The safranin stain is removed

95 / 100

Category: NHPC , Micro Specialization

95. Bacterial spores are detectable in Gram stains as :

a) Dark purple rods

b) Unstained areas within cells

c) Red-pink granules

d) Green fluorescent bodies

96 / 100

Category: NHPC , Micro Specialization

96. Which mechanism is the MOST common for spreading antibiotic resistance among bacteria ?

a) Spontaneous mutation

b) Plasmid transfer via conjugation

c) Efflux pumps

d) Enzymatic deactivation

97 / 100

Category: NHPC , Micro Specialization

97. Micrococcus and Staphylococcus species are differentiated by which test(s)?

a) Fermentation of glucose (OF tube)

b) Catalase test

c) Gram stain

d) All of these options

98 / 100

Category: NHPC , Micro Specialization

98. Graft-versus-host disease (GVHD) occurs when :

a) Host rejects the graft

b) Donor T cells attack host tissues

c) ABO incompatibility exists

d) Immunosuppression is excessive

99 / 100

Category: NHPC , Micro Specialization

99. Which of the following is a disadvantage of ethylene oxide as a sterilising agent ?

a) It is highly penetrating.

b) It is carcinogenic and explosive.

c) It is effective against spores.

d) It is cheap and easy to use.

100 / 100

Category: NHPC , Micro Specialization

100. Urease production is detected by :

a) Bubbling reaction

b) Change to pink color (alkaline pH)

c) Formation of black precipitate

d) Development of green color

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