HES 032 Lecture: Periodical Exam 1 Total points105/105 Acyclovir is effective in treating which viral infection? * Influenza virus Herpesvirus HIV Mumps virus Which of the following is the most resistant to destruction by chemicals and heat? * Mycobacterium tuberculosis - cell wall Escherichia coli - cell membrane Bacillus anthracis - spores COVID-19 - spike proteins Which statement is most accurate regarding the drug depicted in the diagram? it inhibits protein synthesis it inhibits cell wall synthesis disrupt cell membrane inhibits nucleic acid synthesis What do you call the protein component of flagella? flagellin pilin lipoteichoic acid peptidoglycan Anton van Leeuwenhoek: Father of Bacteriology; _________: Father of Antibiotics * Alexander Fleming Selman Abraham Waksman Louis Pasteur Robert Koch Which of the following is mismatched? * QUATS- disrupts cell membrane Iodine- inhibits protein synthesis alcohol - disrupts cell membrane radiation - coagulates proteins Statement 1: Catabolic reactions involve the breaking of chemical bonds and the release of energy. Statement 2: Anabolic reactions involve the formation of bonds, which requires energy. * Only statement 1 is true Only statement 2 is true Both statements are correct Both statements are incorrect Which of the following unique bacteria is mismatched? * R. akari - causes epidemic typhus R. typhi - causes endemic typhus C. trachomatis - causes trachoma O. tsutsugamushi - causes scrub typhus Which animal cell organelle is responsible for processing immature proteins before they are able to perform their functions? ribosomes endoplasmic reticulum golgi complex mitochondria Charles has a history of mumps infection. What is type of nucleic acid does the etiologic agent contain? DNA RNA Both RNA and DNA none of the above What do you call those fungi that can live either in yeast or moulds form depending on growth conditions? Monomorphic Teleomorphic Dimorphic Anamorphic Arrange the actual steps in multiplication of animal viruses. * penetration, adsorption, uncoating, release attachment, uncoating, assembly, release attachment, assembly, biosynthesis, release absorption, penetration, uncoating, assembly, release Saliva contain a lysozyme that can prevent bacterial infection. Which bacterial structure does the enzyme degrade? Murein Nucleoid DNA Cell membrane Capsule Which microorganism has a cell wall made of up chitin? bacteria virus yeast helminths Bacillus anthracis is a gram-positive rod that is the causative agent of anthrax. While, Treponema pallidum is _________ * a gram-negative cocci- causative agent of syphilis a gram-positive short rod- causative agent of syphilis a spirochete- causative agent of syphilis a gram-negative short rod- causative agent of syphilis Which genus of bacteria lacks cell wall? * Mycobacterium Mycoplasma Pseudomonas Staphylococcus A PLHIV patient suffered cryptococcosis. He is treated with fluconazole. What is the mechanism of action of the antifungal mentioned? By binding with cell membrane sterols By interfering with sterol synthesis By blocking mitosis or nucleic acid synthesis none of the above Which antibiotic causes significant neurotoxicity and must be taken in conjunction with pyridoxine (vitamin B6) to prevent these neurologic complications? Rifampin Isoniazid Vancomycin Doxycycline Chloramphenicol A patient diagnosed with bacterial food poisoning reported onset of symptoms 18 hours ago. Which of the following is the most appropriate treatment for this patient? fosfomycin ribavirin metronidazole no antibiotics needed only supportive treatment All of the following bacteria are capable of causing pneumonia, EXCEPT: Chlamydophila pneumoniae Klebsiella pneumoniae Haemophilus pneumoniae Mycoplasma pneumoniae The CO2 incubator must main a level of more than 20% oxygen and 5% CO2 in order to facilitate the growth of anaerobic organism. True False All of the following are characteristics of bacteria, EXCEPT: I. have peptidoglycan cell walls and ribosomes II. have the same size and shape. III. replicate via binary fission and all are motile. IV. are prokaryotic and do not have membrane bound organelles. * I and II III and IV II and III I and IV The current recommended treatment for malaria is: * artemisinin combination therapy pyrantel and mebendazole primaquine and quinine hydroxyquinolones Which theory is most widely accepted explanation for the origin of viruses? * Big Bang theory Coevolution theory Retrograde evolution theory Escaped gene theory Statement 1: Yeasts are unicellular organisms that reproduce by spores. Statement 2: Moulds are multicellular organisms that reproduce by budding. Only statement 1 is true Only statement 2 is true Both statements are incorrect Both statements are correct Which microbial genetic process does sex pili is used for? * transduction conjugation transformation mutation The Lipid A structure on the outer membrane of a gram-negative bacteria facilitates which type of disease? Infectious disease Microbial intoxication Opportunistic infection All of the above lipid A cell wall fimbriae flagella Carson suffered severe flu infection. During his admission he was treated with Amantadine drug. What is the mode of action of the antiviral agent? inhibit nucleic acid synthesis inhibit virus entry inhibit viral assembly inhibit protein synthesis 75-year-old man presents to fever, chills and cough suggestive of pneumonia. A lab test was requested for sputum gram stain. The laboratory analyst mistakenly forgot the decolorization step. If the pneumonia is caused by Streptococcus pneumoniae, how will the bacteria seen on the slide? all of the cells will be purple all of the cells will be colorless all of the cells will lyse, thus no GS results all of the cells will be pink. Which of the following types of media would NOT be used to culture organisms that require increased concentration of oxygen? * selective media complex media enrichment media differential media You saw list of prescription from your friend's pocket. The prescribed drugs were zidovudine and lamivudine. What do you think is your friend illness? * Hepatitis B HIV disease Influenza COVID-19 All are characteristics of bacterial chromosomes, EXCEPT: * long, single and double stranded DNA supercoiled, circular DNA paired with extrachromosomal DNA suspended or embedded in the cytoplasm Sofia suffers diarrhea and vomiting. The stool exam reveals 0-2 trophozoitesof E. histolytica. Which of the following statements describe the etiologic agent? non-motile stage of the parasite non-dividing stage of the parasite infective stage of the parasite feeding stage of the parasite After reading your modules, you were amazed that viruses can be used to kill some bacteria that infect people. Which of the following statements suggest true about the differences between bacteria and viruses? bacteria do not have nucleus, whereas viruses do. bacteria do have ribosomes, whereas viruses don't have one. bacteria replicate via mitosis, whereas viruses replicate via transverse binary fission. bacteria do not have cell wall and plasma membrane, whereas viruses do. Each of the following statements concerning the killing of bacteria is correct EXCEPT: A 70% solution of ethanol kills more effectively than absolute (100%) ethanol. The pasteurization of milk kills pathogens but allows many organisms and spores to survive. Iodine kills by causing the formation of thymine dimers in bacterial DNA. An autoclave uses steam under pressure to reach the killing temperature of 121°C. What family does HIV virus belongs to? * Lentiviridae Rhinoviridae Retroviridae Adenoviridae Louie had a scratch wound on his hand while swimming in the brackish water. After several days, the wound had a foul-smell. A culture was done on the wound exudates. The organism isolated was C. perfringens. Which of the following statements best describes this microorganism? it is a capnophile it is a facultative anaerobe it is an obligate aerobic it is a microaerophilic Other: A 25-year woman presents with fever, chills, and painful urination suggestive of UTI. The Gram-stained smear of urine shows many gram-negative short rods. Which of the following is the correct order of the procedural steps when performing the Gram stain? * Fixation, crystal violet, iodine treatment, alcohol/acetone decolorization, safranin Fixation, crystal violet, alcohol/acetone decolorization, safranin Fixation, crystal violet, iodine treatment, safranin Fixation, safranin, iodine treatment, alcohol/acetone decolorization, crystal violet A 16-year old boy whose CD4 count is lower than the normal experienced Candidiasis, a fungal infection. Which pathogen is most likely the cause of the infection? indigenous microbiota opportunistic pathogen microbial allies saprophytes Staining technique employed in differentiating acid fast from non-acid fast bacteria. Gram stain Ziehl Neelsen stain Albert stain India ink A phase occurs when nutrient depletion or toxic products cause growth to slow until the number of new cells produced balances the number of cells that die, resulting in a steady state Lag phase Log phase Stationary phase Death phase All of the following are major adverse reactions of tetracyclines, EXCEPT: discoloration of tooth enamel photosensitivity aplastic anemia enterocolitis Statement 1: Prokaryotes are considered acellular microbes because they are dependent to host for them to survive and replicate. Statement 2: Prokaryotes are organism that lack a true nucleus. * ONLY Statement 1 is incorrect. ONLY Statement 2 is incorrect. Both statements are correct. Both statements are incorrect. In the Gram stain, the decolorization of Salmonella typhi by alcohol is most closely related to: * Proteins encoded by F plasmids Lipids in the outer cell membrane 70S ribosome Branched polysaccharides in the capsule Which of the following is most likely to be associated with the formation of a bacterial biofilm? * UTI with Escherichia coli Airway colonization in a cystic fibrosis caused by P. aeruginosa Impetigo caused by Staphylococcus aureus Meningitis with Neisseria meningitidis Which of the following reasons why TB bacilli hardly or cannot be visualized using gram stain technique? TB bacilli has large number of pili that absorbs crystal violet TB bacilli has large amount of lipid on its cell wall that prevents entry of primary stain. TB bacilli has capsule and slime layer that prevents decolorization process. TB bacilli is too thin to be stain using gram stain. Which of the following is mismatched? Photoautotrophs: cyanobacteria Chemoheterotrophs: protozoa Photoheterotrophs: green sulfur bacteria Chemoautotrophs: nitrifying bacteria Animal viruses escape from their host cells by either lysis of the cell or budding (non-enveloped viruses). True False All scientists contribute to the development and concept of solid bacterial culture, EXCEPT: * Richard Petri Fanny Hesse Robert Koch Louis Pasteur IU isolated a motile, gram-negative cell. During microscopy, she cannot visualized the nucleus. As senior microbiologist, you presume that this cell has: * mitochondria endoplasmic reticulum golgi apparatuses ribosomes all of the above Group B Neisseria meningitidis is identified as the primary etiologic agent of meningitis Which of the following protects this organism from complement-mediated phagocytosis by neutrophils? * capsule pili cell wall flagella What toxins is released by algae that are poisonous to human and other animals? * mycotoxins phycotoxins neurotoxins aflatoxins Protects from osmotic lysis- cell wall; Protects from phagocytes is ___ * endospore peptidoglycan glycocalyx pili plasma membrane Conidia are produced via ___ * sexual method asexual method both none of the above Identify the labeled (D) cell structure and give its function. cilia - for locomotion pili - for locomotion flagella - for locomotion fimbriae - for locomotion A 54 year-old lady experienced a fever and general weakness. Few days later, she notice a pink patches on one side of her body. She had a history of chickenpox when she was 3-years old. What is the possible etiologic agent? * Epstein-barr virus Herpes-Zoster virus Human papillomavirus HIV All of the following statements are correct concerning the resistance mechanism of antibiotics, EXCEPT: * Resistance genes are rarely transferred by conjugation. R factors are plasmids that carry the genes for enzymes that modify one or more drugs. Resistance to some drugs is due to a chromosomal mutation that alters the receptor for the drug. Resistance to some drugs is due to transposon genes that code for enzymes that inactivate the drugs. All statements are TRUE about types of microorganisms, EXCEPT: I. Fungi have eukaryotic cells and most are unicellular. II. Archaea are prokaryotic organisms that lack peptidoglycan in their cell walls. III. Bacteria are unicellular organisms that replicates by binary fission. IV. Viruses are noncellular entities that consist both DNA and RNA. * I and III II and IV I and IV II and III In transduction, a bacterial cell becomes genetically new following uptake of DNA fragments from the environment. The statement is correct The statement is incorrect The statement is neither valid or invalid Astrazeneca vaccines is made from a weakened version of adenovirus from chimpanzees. Which do you think is true about the characteristics of the virus? * Single stranded positive sense RNA virus Double stranded linear RNA virus Non-eveloped, double stranded DNA virus Double stranded circular DNA virus The vector of malaria infection is: * Aedes mosquito Anopheles mosquito Soft tick Hard tick The ideal antimicrobial agent should: I. kill the growth of bacteria. II. Causes minimal damage to host cell. III. Stable when stored in solid or liquid form IV. Remains inactive in tissues and body fluids * I and II III and IV I and III II and IV Which of the following employ the concept of bioremediation? application of bacteria to farm plants to prevent pest infestation fixation of gaseous nitrogen into usable nitrogen using oil-degrading bacteria to an oil spill production of human hormones such as insulin all of the above A phase which vigorous metabolic activity occurs but cells do not divide. * Log Lag Stationary Death All of the following microorganisms have thick layer of material located outside their cell wall, EXCEPT: I. Klebsiella pneumoniae. II. Pseudomonas aeruginosa. III. Streptococcus aureus. IV. Treponema pallidum * I and II III and IV I and IV II and III What is the oldest known disinfectant that is used to reduce the surgical related infections? * agua oxinada carbolic acid vinegar muriatic acid Which statement is INCORRECT? * Chloramphenicol affects the large subunit of the bacterial ribosome, which is different from the large subunit of the human ribosome Sulfonamides affect folic acid synthesis in bacteria, a pathway that does not occur in human cells. Isoniazid affects the DNA polymerase of bacteria but not that of human cells Penicillins affect bacteria rather than human cells because bacteria have a cell wall, whereas human cells do not. A breast surgery was done in the OR with a hepatitis B positive patient. What do you think is the best disinfectant to be used after the procedure? * ethyl alcohol hypochlorite lysol chlorhexidine Which of the following pairs is mismatched? cocci: Neisseria bacilli: Escherichia spirochetes: Mycobacterium rods: Actinobacillus Match the following: Proteus vulgaris - peritrichous flagella.; Leptospira interrogans - _______ * monotrichous flagella cilia axial filaments fimbriae Acanthamoeba and Naegleria species move by means of which cell structures? * cilia flagella pseudopodia they don't move at all. Clostridium botulinum causes the disease botulism by producing toxin. The gene encoding the toxin is integrated into bacterial genome during lysogenic conversion. The toxin gene was acquired by which process? * conjugation transduction transformation transposition A 45-year-old farmer presents with muscle atrophy, and declining cognitive function. His favorite food is pig brain soup which he has eaten almost every week since he was 15 years old. Which of the following best describes the most likely etiologic agent of his symptoms? capsid containing virus a cyst forming organism an abnormally folded protein unicellular organism with nucleoid containing DNA All diseases are caused by infectious particles, EXCEPT: I. Dengue and Zika. II. Mad Cow disease and Creutzfeldt-Jakob disease. III. HIV/AIDS and Anthrax IV. COVID-19 and Plague * I and II III and IV I and III II and IV All but one are treatment for helminthic (roundworms and flatworms) infections. * Mebendazole Metronidazole Praziquantel Pyrantel pamoate Tracheal aspirate from a patient with hospital-acquired pneumonia reveal the presence of methicillinresistantStaphylococcus aureus (MRSA). Which of the following drugs is the best empiric treatment? * penicillin G ampicillin vancomycin rifamycin A 30-year-old male who is a sexually and active IV drug user developed fever, nausea, and jaundice. Laboratory test reveals elevated liver enzymes but normal CD4 count. Which of the following best characterizes the virus most likely causing her illness? * DNA virus belonging to the Hepadnaviridae ss(+)RNA virus belonging to the Flaviviridae ss(+)RNA virus belonging to the Hepeviridae RNA virus belonging to the Lentiviridae Latent infection of neurons occurs with which of the following viruses? * HSV EBV Measles virus HIV Rabies virus During an outbreak of gastrointestinal disease caused by an Escherichia coli strain sensitive to ampicillin, tetracycline, and chloramphenicol, a stool sample from one patient yields E. coli with the same serotype resistant to the three antibiotics. * Transduction Conjugation Transformation Transposition Your patient is a 75-year-old man who is several days post-op following removal of her carcinoma of the colon. He now spikes a fever and has a cough, and a chest X-ray shows pneumonia. While being treated with the appropriate antibiotics, he develops severe diarrhea. You suspect he may have pseudomembranous colitis. Which one of the following is the best antibiotic to treat the infection? * Vancomycin Ceftriaxone Metronidazole Doxycycline A vaginal swab culture from a 35-year-old pregnant woman produced colonies on blood agar. The colonies are described as medium size with small, diffuse zones of β-hemolysis. What do you think is the classification of blood agar according to function based on the case presented? * Differential Selective Enrichment Enriched Statement 1: Once it enters a host cell, a virulent bacteriophage always initiates the lytic cycle and undergo absorption and penetration. Statement 2: The third step of bacteriophage lytic cycle is biosynthesis where phage parts are assembled to create another copy. * Statement 1 and 2 are correct Statement 1 and 2 are incorrect Only statement 1 is incorrect Only statement 2 is incorrect Rotavirus, Campylobacter jejuni and Entamoeba histolytica are all microbes that causes diarrhea. Which one of the following agents contains either DNA or RNA but not both? * Campylobacter jejuni Entamoeba histolytica Rotavirus none of the above
