1. Most common virus implicated in Severe Acute Respiratory Syndrome (SARS) isCorona VirusInfluenza VirusPicorna VirusHerpes Virus 2. Acellular pertusis vaccine contains -Pertactin, flagillary hemagglutinin, cytotoxin, endotoxinPertactin, flagillary hemagglutinin, fimbriae, endotox inPertactin, cytotoxin, fimbriae, pertactin,Flagillary hemagglutinin, pertusis toxin, fimbriae 3. Brucella is transmitted by all expect:Through the placenta of animalsAerosol transmissionPerson to personEating uncooked food 4. Virulence in gram negative bacteria is due toPiliLipid APeptidoglycanTeichoic acid 5. Gram stained periorbital exudates in severe panophthalmitis with cellulitis in an elderly diabetic shows irregular branching aseptate and broad hyphae. Which of the following is the most likely diagnosis:CandidaAspergillusPenci]liumApophysomyces sp 6. All are true about brucella except -B. abortus is capnophilicTransmission by aerosol can occur occasionallyPasteurisation destroys it2ME is used to detect IgA 7. Immunoglobulin bound on the surface of bacteria mediates phagocytosis by (Phagocytosis causes complement activation by)-C3b and FcReceptor mediated endocytosisOxidase actionLysosmal burst 8. How do you differentiate between Streptococcus and Staphylococcus infectionBacitracin testCatalase testOpotochin testCoagulase test 9. Which cellular organelle listed below contains specialized enzymes whose functions involve hydrogen peroxide?MitochondriaMicrobodyNucleusGolgi complex 10. A positive tuberculin test always indicates which of the following?Active tuberculosisChronic tuberculosisHypersensitivity to tuberculoproteinsNo exposure to tuberculosis 11. Certain enzymes are responsible for suppuration, These enzymes derive chiefly fromSerumTissue.Neutrophils.lymphocytes. 12. Which of the following represents the characteristic cellular infiltrate in delayed type hypersensitivity?T cells and macrophagesEosinophilsNeutrophilsB cells and plasma cells 13. Bacterial capsule is stained byIndia ink stainAlberts stainNeisser's stainPonder's stain 14. A male patient presented with granulomatous penile ulcer. On Wright geimsa stain tiny organisms of 2 microns within macrophages seen. What is the causative organism?LGVCalymmatobacterium granulomatisNeisseriaStaph aureus 15. A child presents with recurrent episodes of sinopulmonary infection by bacteria with polysaccharide rich capsules. Which of the following subclass deficiency of immunoglobulins s likely to cause such infections:IgAIgG1IgG2IgA + IgG1 16. In myasthenia gravis, autoantibodies are directed against which of the following structures?SarcomereMyofasciaMyocyte nucleusAcetylcholine receptor 17. Which of the following are used in protective vaccines because they retain their antigenicity but have lost their toxicity?AntitoxinsToxoidsMycotoxinsEndotoxins 18. Bull-neck' is seen in severe cases of which of the following?DiphtheriaTubercular lymphadenitisMumpsGoitre 19. Which of the following is false about clostridium perfringes -Food poisoning causing strains of cl. perfringes produce heat resistant SporesShow positive naegler reactionMost important toxin is hyaluronidaseCl. perfringes is the most common cause of gas gangrene 20. Which of the following cell types are the most potent activators of naive T cellsB cellsFollicular Dendritic cellsMature Dendritic cellsMacrophages 21. Which is not true about vibrio choera:It is non halophilicGrows on simple mediaMan is the only natural hostCannot survive in extracellular environment 22. Not used in leptospirosis -Microscopic agglutination testDark field illuminationMacroscopic agglutination testWeil felix reaction 23. A deficiency in which of the following cells can predispose to candidiasis?ABasophilsEosinophilsMacrophagesT lymphocytes 24. Which of the following is not a rapidly growing atypical mycobacteria causing lung infectionsM. chelonaeM.fortuitumM.abscessusM.kansasii 25. Lambda phage which of the following is trueIt causes mad cow diseaseLysogenic to lytic conversion cannot occurLysogenic inform incorporates in host DNA & remain dormantLytic phase incorporates in host DNA, proliferate & causes rupture of cell 26. Which of the following chemical agents has the broadest antimicrobial spectrum of activity?PhenolEthanolLsopropanolGlutaraldehyde 27. The main advantage of active immunity is that resistance is:Available immediatelyShort termLong termNone of the above 28. The phase of growth in which bacteria increases in size with increase in metabolic activity but no increase in number is seen inPratella phaseLag phaseLog phaseDecline phase 29. Bacterial vaccines are composed of:Capsular polysaccharidesInactivated protein exotoxins (toxoids)Live attenuated bacteriaAll of the above 30. With reference to Bacteroides fragilis, all of the following statements are true exceptB. fragiIis is-the most frequent anaerobe isolated from clinical samplesB fragilis is not uniformly sensitive to MebronidazoleLipopolysaccharide formed by B. fragilis is structurally and functionally different from the conventional endotoxinShock and DIC are common in Bacteriodes bacteremia 31. Lysozyme degrades:PeptidoglycanRNA polymeraseLipopolysaccharideChitin 32. If Type A blood is accidentally transfused into a Type B recipient, the immediate haemolytic reaction would be the result of which of the following?IgM against the A antigenIgA against the A antigenlgG against the B antigenT cytotoxic cell activation 33. Which of the following statements regarding Legionella pneumonia is trueAspiration is an important mode of transmissionLegionella antigens in the urine is the gold standard of diagnosisLegionnaires disease is also known as Pontiac feverHigh Person to Person transmission 34. An elderly patient presented with fever, chest pain and dry cough. Sputum cultured on charcoal yeast medium, the organism is -H. influenzaMoraxella catarrhalisLegionellaBurkholderiacepacia 35. In a 5 year old boy who has history of pyogenic infections by bacteria with polysaccharide-rich capsules, which of the following investigations should be done?IgA deficiencyIgG1 deficiencyIgG2 deficiencyIgA and IgG2 deficiency 36. Most common cause of Zoonotic Cutaneous Leishmaniasis isL. TropicaL. MajorL. DonovaniL. Brazilensis 37. The causative agent for Delhi Boil isL. TropicaL. DonovaniL. BrazilensisL. Mexicana 38. In Which of the following organs or tissues are ascending infections common?BoneHeartKidneyPeritoneum 39. The antigen-binding site of antibody molecules is localized in theFab fragmentFc receptorJ- chain.constant region 40. What will happen if a bacteria acquires genes coding for restriction endonuclease -Bacteria will die as lacks methylaseIt will damage the host cellIt will have capacity to divide & multiple many timesEnhances proof reading activity of that bacteria 41. An infection is epidemic if:It has a worldwide distributionIt is constantly present at a low level in a specific populationIt occurs much more frequently than usualIt is highly communicable 42. All of the following statements about Parvovirus B- 19 are true, Except:<10% spread by transplacental routeRespiratory route is the primary mode of transmissionIt is a DNA virusAffects erythroid progenitors 43. Which of the following statement is true about bacteriophageIt is a bacteriumIt helps in transformationIt imparts toxigenicity to bacteriaIt transfers only chromosomal gene 44. All of the following statements concerning bacterial plaque are true, except:It is the key etiologic agent in the initiation of gingivitis and periodontal diseaseIt is an accumulation of a mixed bacterial community in a dextran matrixIt forms on a cleaned tooth within minutesIt is composed of solids (80%; 95% of which are bacteria) and water (20%) 45. All of the following statements concerning complement are true, except:It is a collective term for a group of serum proteins that is the primary mediator of antigen-antibody reactionsThese proteins participate in lysis of foreign cells, inflammation, and phagocytosisIt consists of at least 11 different proteinsThe proteins are synthesized mainly by the kidney 46. HIV pt with malabsotion, fever, chronic diarrhoea, with acid fast positive organism. What- is the causative agentGiardiaMicrosporidiaIsosporaE. histolytica 47. Ideal method for sterilization of electric equipment's flexible endoscopesChemical vapourIonizing radiationInfrared radiationEthylene oxide 48. Aerosol spread leading to epidemics is seen in infection withLegionellaHemophilusInfluenzaMycoplasma 49. Which of the following viral diseases has the LONGEST incubation period?Herpetic gingivostomatitisCommon coldInfluenzaRabies 50. Anaphylotoxins:Produce inflammationCause enhanced capillary permeabilityInduce smooth muscle contractionAll of the above 51. Epstein Barr virus causes autoimmunity by:Molecular MimicryRelease of Sequestrated AntigenInappropriate Expression of MHC Class II MoleculesPolyclonal B cell Activation 52. Vaccination is based on the principle of:AgglutinationPhagocytosisImmunologic MemoryClonal detection 53. First immunoglobulin increased during immunityIgGIgAIgMIgD 54. Optimal time and temperature required for sterilization in an autoclave is133 degree centigrade for 15 mts, 15 lbs121 degree centigrade for 15 mts, 15 lbs121 degree centigrade for 20 mts, 15 lbs121 degree centigrade for 15 mts, 5 lbs 55. Ovalbumin was injected into a Rabbit. Which of the following classes of Antibiotics are likely to be produced initially:IgGIgMIgEIgD 56. Which of the following immunoglobulins is a pentamerIg AIg DIg GIg M 57. Edema in filariasis is due toOncotic pressureLympatic obstructionHydrostatic agentCapillary hydrostatic pressure 58. Which of the following statements about campylobacter jejuni is falseCommonest agent responsible for campylobacterosisPoultry is a common source of infectionHumans are important reservoirs of infectionAssociated with Guillain Barre Syndrome 59. Organism involved in Cysticercosis of oral cavityEchinococcus granuLosusTaenia soLiumHook wormLymphogranuloma venerum 60. Leukotrienes C4, D, and E4 are collectively known as:HistamineSlow-reacting substances of anaphylaxis (SRS-As)HeparinSerotonin 61. Reassortment is seen in -AstronovirusRotavirusHepadnavirusHerpesvirus 62. Hepatitis B infectivity isAnti HbsAg & HbcAgHbs AgHBV DNA & HbeAgAnti HbcAg & Hbs Ag 63. The first virological marker following acute hepatitis B infection isAnti Hbs AgIgM Anti Hbc AgHbsAgAnti Hbe Ag 64. Marker for chronic persistent HBV infection isIgM anti-HBcHBsAgHBeAgAnti HBsAg 65. Successful immunization with a hepatitis B vaccine results in the development of serum antibodies to which of the following?HBsAgHBcAgHBeAgHBV-DNA polymerase 66. All of the following agents have polysaccharide capsule related antigen antibody responses, except:PneumococcusMeningococcusHaemophillus InfluenzaBordetella Pertusis 67. The basic chemical structure of endotoxins includes which of the following?Capsular polysaccharideAcid stable peptidoglycanH and L chain glycoproteinsSomatic O polysaccharide, core polysacchande, lipid A 68. Neonatal sepsis is not caused by -Staphylococus aureusE.coliGroup B streptococciAcintobacter 69. XenograftGrafts transferred from genetically similar individualsAnimalGraft taken and transferred from one species to another speciesGrafts taken from one place and replaced in another position in the same individual 70. Which of the following disinfectant is effective against herpes simplex viruses but NOT rhinoviruses?PhenolicsLodophoresGlutaraldehydes70% isopropyl alcohol 71. Eosinophils are characteristically seen in which of the following conditions?Bacterial infectionsViral infectionsFungal infectionsParasitic infestations 72. Most sensitive test for Treponema -VDRLRPRFTA-ABSKahn 73. Which of the following is a powerful oxidizing agent that inactivates bacteria and most viruses by oxidizing free sulfhydryl groups?AlcoholChlorineFormaldehydePhenol 74. Regarding IgE, which of the following is false?Causes anaphylaxisImmediate reactionFix complementCross placenta 75. All are true regarding disinfectants except -Glutaraldehyde is sporicidalHypochlorites are virucidalEthylene oxide is intermediate disinfectantPhenol usually requires organic matter to act 76. Which of the following is an antimicrobial agent that primarily inactivates cellular DNA?PhenolsChlorhexidineEthylene oxide70 percent isopryl alcohol 77. Best method to disinfect delicate instruments as endoscope, cystoscopes and metallic instrument is byChemical vapourInfrared radiationEthylene gasFiltration 78. Antigen antibody precipitation is maximally seen in which of the followingExcess of antibodyAntigen Hapten interactionExcess of antigenEquivalence of antibody and antigen 79. Which of the following commonly produces a positive heterophile antibody test?AdenovirusCytomegalovirusEpstein-Barr virusParainhluenza virus 80. Visceral larva migrans is caused byLoa-loaToxocaraEntrobius vermicularisTinea 81. A young male presents with loose motions and 'intermittent abdominal pain over the past ,1 year Wet mount stool specimen showed the presence of multiple ova which are more than 100? in diameter. The causative organisms for the disease shall not includeFasciola giganticaGastrodiscoides hominisEchinostima ileocaanumOpistorchis viverini 82. Alcohol requires which concentration listed below to kill bacteria given sufficient time?10%-20%30%-40%50%-60%70%-95% 83. Infective dose of Salmonella Typhi is:One bacillus1 to 10 bacilli102 to 105 bacilli108 to 1010 bacilli 84. Synthesis of an immunoglobulin in membrane bound or secretory form is determined by:One turn to two turn joining ruleClass switchingDifferential RNA processingAllelic exclusion 85. Hereditary angioedema is the result of which of the following?Lack of a thymusDeficiency in C1 esterase inhibitorDevelopmental arrest of lymphocytesDefective VH gene recombination to DJH 86. Which of the following infections is not associated with congenital malformationsRubellaNeisseriaCytomegalovirusToxoplasma 87. Which of the following is most resistant to antiseptics:SporePrionCystFungus 88. All of the following protozoa may be detected by Fecal Acid Fast Stain, exceptCryptosporidiumIsosporaCyclosporaMicrosporidia 89. Which of the following is the most common fungal infection in immunocompetent patient:CandidaAspergillusCryptococcusPenicillium 90. Sputum can be disinfected by all except:AutoclavingBoilingCresolChlorhexidine 91. Diagnostic of Rabies -Guarneri bodiesNegri bodiesCowdry A bodyBollinger bodies 92. Rabies is identified byGuarneri bodiesNegri bodiesCowdry A bodiesCowdry B bodies 93. Which of the following is a method for acquiring infection by Legionella pneumophilaConsumption of contaminated waterBreathing aerosols of environmental water sources such as air conditioning unitsConsumption of-contiminated meat and meat productsClose contact with carrier of Legionella 94. Transfer of genetic information between DNA molecules inside a cell is calledTranspositionTransformationConjugationDuplication 95. With reference to antibiotic resistance all of following statements are true except -The most common mechanism is production of neutralizing enzymes by bacteriaPlasmid mediated resistance is exclusively transferred verticallyComplete elimination of target is the mechanism by which enterococci develop resistance to vancomycinAlteration of target lesions leads to development of resistance to antibiotics in Streptococcus pneumonia 96. T lymphocytes are MOST directly involved in which of the following?Immediate hypersensitivityImmune complex injuryComplement synthesisContact dermatitis 97. Which of the following represents the phenotypic expression of both alleles in a gene pairPenetranceLyonizationCodominanceHybridization 98. Which of the following has been shown to be the most effective antimicrobial agent for reducing plaque and gingivitis long-term?Stannous fluoridePhenolic compoundsChlorhexidineQuaternary ammonium compounds 99. Non supparative lesion caused by group-A StreptococciNecrotizing fasciitisImpetigoCellulitisPoststreptococcaL Glomerulonephritis 100. Which of the following statements about Pneumococcus is false:Capsule aids in virulenceCommonest cause of Otitis mediaCauses mild forms of meningitisRespiratory tract of carriers is most important source of infection Loading...