TOP Microbiology MCQS
All Questions for: TOP Microbiology MCQS
Question 1: Bacterial spores are destroyed by_______________?
- A Pasteurisation
- B Boiling at 100
- C Disinfection by hypochlorite solution
- D Autoclave
Explanation: The correct answer to the question is: Autoclave
Question 2: The interaction of antigens with antibodies on the surface of a mast cel leads to degranulation and anaphylaxis. The mast cell granules produce anaphylaxis because they contain________________?
- A Proteolytic enzymes
- B Vasoactive mediators
- C Lysosomes
- D Lymphotoxins
Explanation: The correct answer to the question is: Vasoactive mediators
Question 3: Bacteria with potent exotoxin is_______________?
- A Klebsiella
- B Pseudomonas
- C Clostridium tetani
- D Shigella
Explanation: The correct answer to the question is: Clostridium tetani
Question 4: True about prions________________?
- A Viruses which are genetically deficient
- B Phase in which virus cannot be demonstrated in host cell
- C Composed largely proteins without any nucleic acid
- D Viral components may be synthesized but maturation & assembling is defective
Explanation: The correct answer to the question is: Composed largely proteins without any nucleic acid
Question 5: The best skin disinfectant is________________?
- A Savlon
- B Alcohol
- C Chlorhexdine
- D None of the above
Explanation: The correct answer to the question is: Chlorhexdine
Question 6: Presence of HBe Ag in patients with hepatitis indicates_____________?
- A Simple carriers
- B Late convalescence
- C High infectivity
- D Carrier status
Explanation: The correct answer to the question is: High infectivity
Question 7: The facultative anaerobic bacteria are those who are_______________?
- A Unable to grow in the presence of oxygen
- B Able to grow in the presence of absence of oxygen
- C Able to grow in the presence of carbon dioxide
- D Unable to grow in the absence of oxygen
Explanation: The correct answer to the question is: Able to grow in the presence of absence of oxygen
Question 8: A 30 years old patient developed high fever of sudden onset. Peripheral blood smear showed cresent shaped gametocytes. Malaria pigment was dark brown in colour Which of the following malarial parasites is the causative agent ?
- A Plasmodium ovale
- B Plasmodium vivax
- C Plasmodium falciparum
- D Plasmodium malaria
Explanation: The correct answer to the question is: Plasmodium falciparum
Question 9: Erysipelas is caused by________________?
- A Group B staphylococci
- B Group A steptococci
- C Pneumococci
- D Gonococci
Explanation: The correct answer to the question is: Group B staphylococci
Question 10: True about immune response of hepatitis B is__________________?
- A Antibody to HBC is not protective
- B CMI disappears soon after recover
- C Highest titres of anti HBC are found in persistent carriers of HBs Ag
- D Antibody of HBs Ag is associated with resistance to infection
Explanation: The correct answer to the question is: Antibody of HBs Ag is associated with resistance to infection
Question 11: Culture medium for corynebacterium diphtheria______________?
- A Lowenstein Jensen Medium
- B Loefflers serum slope
- C Mc Conkey
- D Saborauds agar
Explanation: The correct answer to the question is: Loefflers serum slope
Question 12: A full course of immunization agianst. Telanus with 3 doses to Tetanus toxoid, confers immunity for how many years ?
- A 20
- B 15
- C 5
- D 10
Explanation: The correct answer to the question is: 10
Question 13: Which of the following methods is adopted for screening HIV infection ?
- A ELISA followed by western blot technique
- B Western blot followed by ELISA
- C Polymers chain reaction
- D Virus isolation
Explanation: The correct answer to the question is: ELISA followed by western blot technique
Question 14: Sclerotic bodies measuring 3-5m in size, multi-septate, chestnut, brown color is characteristic of________________?
- A Histoplasmosis
- B Chromoblastomycosis
- C Rhinosporodiosis
- D Phaeohypomycosis
Explanation: The correct answer to the question is: Chromoblastomycosis
Question 15: The best way of detecting the presence of viruses in the infected cell
- A Haemagglutination inhibition test
- B Presence of viral protein in the infected monolayer
- C Cytopathic changes in culture cells
- D Haemagglutination test
Explanation: The correct answer to the question is: Cytopathic changes in culture cells
Question 16: An oxidase-positive, gram-negative rod which produces a bluish-green pigment has been grown in culture from a swab obtained from an infected burn wound. This organism is susceptible to gentamicin, ticarcillin and tobramicin, but resistant to all the other antibiotics which of the following organisms is it likely to be ?
- A Proteus miribilis
- B Pseudomonas aeruginosa
- C Escherichia coli
- D Klebsiella pnemoniae
Explanation: The correct answer to the question is: Pseudomonas aeruginosa
Question 17: Exaltation is________________?
- A No change
- B Increased Virulence
- C Decreased virulence
- D None
Explanation: The correct answer to the question is: Increased Virulence
Question 18: Which of the following is not true of boiling water_____________?
- A Used for sterilizing surgical instruments
- B Can kill vegetative bacterial cells
- C Can kill mycobacterium tuberculosis
- D It can kill hepatitis B virus
Explanation: The correct answer to the question is: Used for sterilizing surgical instruments
Question 19: The type of immunoglobulin most commonly increased in multiple myeloma is_______________?
- A IgA
- B IgD
- C IgG
- D IgM
Explanation: The correct answer to the question is: IgG
Question 20: Germ tubes are formed mainly by_______________?
- A Candida albicans
- B Candida tropicalis
- C Candida pseudotropicalls
- D Candida stellatoidea
Explanation: The correct answer to the question is: Candida albicans
Question 21: The best method of sterilization of dressing powder is_____________?
- A Inspissation
- B Hot air oven
- C Autoclaving
- D Tyndallization
Explanation: The correct answer to the question is: Hot air oven
Question 22: The protective effects breast milk are known to be associated with______________?
- A Mast cells
- B IgM antibodies
- C IgA antibodies
- D Lysozyme
Explanation: The correct answer to the question is: IgA antibodies
Question 23: Loss of capsule in bacteria is generally associated with______________?
- A Inability to spread through tissue
- B Loss of infectivity
- C increase in invasiveness
- D Decease in virulence
Explanation: The correct answer to the question is: Decease in virulence
Question 24: Dark ground microscopy is useful to identify______________?
- A Mycoplasma
- B Chlamydiae
- C Spirochaetes
- D Rickettsiae
Explanation: The correct answer to the question is: Spirochaetes
Question 25: Most common opportunistic infection in AIDS is_____________?
- A Tuberculosis
- B Candidiasis
- C Cryptococcosis
- D Aspergilosis
Explanation: The correct answer to the question is: Candidiasis
Question 26: Which of the following immunoglobulins has the highest mean serum concentration in humans_________________?
- A IgG
- B IgA
- C IgM
- D IgD
Explanation: The correct answer to the question is: IgG
Question 27: Dry heat destroys microorganisms by_____________?
- A Coagulation of proteins
- B Oxidation
- C Hydrolysis of DNA
- D Lysis
Explanation: The correct answer to the question is: Oxidation
Question 28: Which of the following is true about pasteurization ?
- A Tubercle bacilli are destroyed
- B It kills all bacteria except thermoduric bacteria
- C It kills bacteria and spores
- D It kills 95% of microorganisms
Explanation: The correct answer to the question is: It kills all bacteria except thermoduric bacteria
Question 29: Flash pasteurization of milk is done at what temperature______________?
- A 60
- B 72
- C 72
- D 125
Explanation: The correct answer to the question is: 72
Question 30: patients with organ transplants are most frequently infected with______________?
- A CMV
- B Hepatitis B
- C EBV
- D Hepatitis A
Explanation: The correct answer to the question is: CMV
Question 31: The viral action is differentiated from bacterial action by_________________?
- A Toxin production
- B Lymphocytes production
- C Neutrophils production
- D Interferon production
Explanation: The correct answer to the question is: Interferon production
Question 32: Which organism causes prosthetic valve endocarditis within 60 days of surgery________________?
- A Streptococcus Viridans
- B Fungus
- C Staphylococcus aureus
- D Staphylococcus epidermis
Explanation: The correct answer to the question is: Staphylococcus epidermis
Question 33: Hospital dressing is best disposed by_____________?
- A Burying
- B Autoclaving
- C Incineration
- D Dumping
Explanation: The correct answer to the question is: Incineration
Question 34: Salivary peroxidise system is known to be effective agianst________________?
- A Lactobacillus acidophilus
- B Streptococcus mutans
- C Veilonella parvula
- D Actinomyces viscosus
Explanation: The correct answer to the question is: Lactobacillus acidophilus
Question 35: Secretory piece of IgA is synthesized in______________?
- A T-cells
- B Mucosal epithelium
- C B-cells
- D Lymph nodes
Explanation: The correct answer to the question is: Mucosal epithelium
Question 36: Cysticercosis celluosae is caused by_____________?
- A Echinococcus granulosus
- B T. Saginata
- C T. Solium
Explanation: The correct answer to the question is: T. Solium
Question 37: Borelia vincenti is a______________?
- A Mycoplasma
- B Chlamydia
- C Spirochaete
- D Mycobacteria
Explanation: The correct answer to the question is: Spirochaete
Question 38: Hot air oven cannot be used for sterlisling___________________?
- A Needles
- B Culture media
- C Instruments
- D Clothes
Explanation: The correct answer to the question is: Culture media
Question 39: Cold sterilization refers to the process of sterilization by use of____________________?
- A Gamma rays
- B Infrared rays
- C Ultrasonic vibrations
- D Ultra violet rays
Explanation: The correct answer to the question is: Gamma rays
Question 40: Which one of the following enteric organisms is anaerogenic and non motile ?
- A Klebsiella pneumonia
- B Salmonella typhi
- C Proteus mirabilis
- D Shigella sonnei
Explanation: The correct answer to the question is: Shigella sonnei
Question 41: Common inhabitant of throat and tonsils is______________?
- A Beta hemolytic streptococci
- B Alpha hymolytic streptococci (S. viridans)
- C Staphylococci
- D Pneumococci
Explanation: The correct answer to the question is: Alpha hymolytic streptococci (S. viridans)
Question 42: Enterically transmitted NANB hepatitis B_____________?
- A Hepatitis C
- B Hepatitis F
- C Hepatitis E
- D Hepatitis D
Explanation: The correct answer to the question is: Hepatitis E
Question 43: Hot air oven is used for sterilization of all EXCEPT__________________?
- A Glassware
- B Sharp instrument
- C Rubber tubes
- D Liquid paraffin
Explanation: The correct answer to the question is: Rubber tubes
Question 44: Which worm is longest________________?
- A Hook worm
- B T. Saginata
- C A. Lumbricoides
- D T. Solium
Explanation: The correct answer to the question is: T. Saginata
Question 45: Malignant pustule is referred to_________________?
- A Cutaneous anthrax
- B Facio-cervical actinomycosis
- C Infected squamous cell carcinoma
- D None of the above
Explanation: The correct answer to the question is: Cutaneous anthrax
Question 46: In which of the following immunization is given after infection is started________________?
- A Influenza
- B Rabies
- C Poliomyelitis
- D Herpes
Explanation: The correct answer to the question is: Rabies
Question 47: True about VDRL test________________?
- A Non
- B Best followed for drug therapy
- C Slide flocculation test
- D All of the above
Explanation: The correct answer to the question is: All of the above
Question 48: A young pregnant woman presents with fulminant hepatic failure. The most likely aetiological agent is_____________?
- A Hepatitis B virus
- B Hepatitis E virus
- C Hepatitis C virus
- D Hepatitis A virus
Explanation: The correct answer to the question is: Hepatitis E virus
Question 49: Lancefields classification of B hemolytic streptococcus is based on______________?
- A M Protein
- B Physiological properties
- C Polysaccharide C antigen
- D Type of lipid in cell membrane
Explanation: The correct answer to the question is: Polysaccharide C antigen
Question 50: Virulence of Gonococcus is due to___________________?
- A Cell Membrane
- B Its intracellular location
- C Pili
- D Cytolytic enzymes
Explanation: The correct answer to the question is: Pili