MCQ Bacteriology Archives • Page 2 of 2 • Microbe Online

MCQ Bacteriology 11 The survival of Mycobacteria after ingestion by macrophages is attributed toa. Bacterial inhibition of complement activation via the alternative pathway.b. Bacterial inhibition of phagolysosome formation and interference with endosomal acidificationc. The poor immunogenicity of the cell wall glycolipids.d. The bacterium's rapid escape from the endosome into the cytoplasm of infected cells.e. The bacterium's resistance to oxygen-active radicals released into the phagolysosome. MCQ Bacteriology 12 A 21 year newly married woman developed a urinary tract infection (UTI). At the time she sought medical advice, she was febrile and complained of painful urination and flank pain. Her urine appeared “cloudy”. Urine culture yields a lactose-fermenting, indole-positive, Gram-negative bacillus. The infectiveness of the organism responsible for this urinary tract infection is associated with specific,a. Exotoxinsb. K antigensc. Metabolic propertiesd. P fimbriaee. Plasmids MCQ Bacteriology 13 The role of bacterial capsules as virulence factors is usually related to their ability to interfere witha. Antibody bindingb. B lymphocyte activationc. Antibacterial penetration of bacterial cellsd. Phagocytosise. The release of interferon-gamma and other macrophage activating cytokines MCQ Bacteriology 14 A mutation in DNA gyrase is likely to result in resistance to which one of the following antibiotics?a. Amphotericin Bb. Ciprofloxacinc. Penicillind. Rifampine. Streptomycin MCQ Bacteriology 15 Resistance of Staphylococcus aureus to methicillin is most often caused bya. alternation of the major target for the drugb. cell membrane impermeabilityc. decreased uptake of the antibioticd. Inactivation of autolysinse. synthesis of a potent Beta-Lactamase MCQ Bacteriology 16 The molecular basis for the effect of cholera toxin on duodenal mucosal cells isa. activation of adenylate Cyclaseb. inactivation of a G1 proteinc. increased activity of potassium pumpsd. increased generation of cyclic adenosine monophosphate (cAMP)e. ribosylation of guanosine triphosphate (GTP) binding protein. MCQ Bacteriology 17 The synthesis of erythrogenic toxin by specific strains of group A Streptococcus is determined by aa. bacterial chromosomal geneb. gene carried by a lysogenic phagec. specific virulence plasmidd. Transposon MCQ Bacteriology 18 Which one of the following factors, released by heating a suspension of sheep erythrocytes, is required for the growth of Haemophilus Influenzae in chocolate agar?a. Coagulaseb. Nicotinamide adenine dinucleotide (NAD)c. Hemoglobind. Hemolysine. Protein A MCQ Bacteriology 19 Which one of the following bacteria is most likely to be relatively resistant to antibiotics as a result of the relative impermeability of its cell wall?a. Haemophilus influenzaeb. Pseudomonas aeruginosac. Staphylococcus aureusd. Streptococcus pneumoniaee. Streptococcus pyogenes MCQ Bacteriology 20 A patient develops explosive, watery diarrhea 24 hours after eating seafood. What bacterium is most likely involved?a. Campylobacter fetusb. Salmonella typhimuriumc. Shigella flexnerid. Vibrio choleraee. Vibrio parahaemolyticus Answers Key 11. b. Bacterial inhibition of phagolysosome formation and interference with endosomal acidification 12.d. P fimbriae 13.d. Phagocytosis 14.b. Ciprofloxacin 15.a. Alternation of the major target for the drug (i.e. Penicillin Binding Proteins) 16.d. increased generation of cyclic adenosine monophosphate (cAMP) 17.b. gene carried by a lysogenic phage 18.b. Nicotinamide adenine dinucleotide (NAD) i.e. Factor V 19. c. Staphylococcus aureus 20. e. Vibrio parahemolyticus (It is commonly found in brackish/saltwater of sea). Note:Find MCQ Bacteriology Questions (21-30) HERE