Microbiology Exam 3 Questions with correct Answers

Microbiology Exam 3 Questions with correct Answers Aspergillus and histoplasmosis infections are both caused by Inhalation of fungal spores All of the following are true about cholera toxin except that it Is an endotoxin Which of the following is evidenced by the health of gnotobiotic mice? The presence of normal microbiota challenges the immune system All of the following are ways pathogens avoid destruction by the host immune system EXCEPT: Toxin production Ways pathogens avoid destruction of the immune system... Antigenic Variations - Triggering Apoptosis - Capsules Lobed amebas and filamentous amebas are differentiated by the form of their (pseudopod) Which of the following characteristics of the rabies virus is most important for it's classification? Single stranded, negative-sense RNA genome Which of the following is true regarding the herpes virus? Latent herpes virus DNA produces microRNAs that interfere with apoptosis Which of the following forms of treatment does not evolve as pathogens evolve? Antibiotics Which of the following mechanisms does an ameba use for locomotion? Pseudopods All of the following are true about bacterial capsules except: They are produced by intracellular pathogens to avoid the host immune system Which of the following is NOT a level of viral evolution? Within an organelle. Levels of viral evolution: within an individual organism.. within a host community.. within a viral species population What is problematic about treating bacterial infections that have spread to the brain? Many antibiotics are not capable of penetrating the blood brain barrier West Nile virus is capable of infecting many different organisms (humans birds raccons) and , Has a broad host range The preferred carbon source for epithelial cells is Butyrate What would be the expected aerobe and anaerobe ratio of the belly button? 1:10 One positive aspect as viruses is their function as Cloning vectors According to the figure below which of the following is true about Coxiella? Coxiella prevents phagosome-lysosome fusion All of the following are possible when considering a new pandemic influenza strain except Avian influenza strains can be directly transmitted to other host species, such as humans Which of the following is consistently sampling normal bacteria of the host to maintain a low level immune response? Lymphoid tissue All of the following are required for disease to occur.. What is the second step in microbial pathogenesis? Tissue attachment Which of the following organisms lacks the ability to do aerobic cellular respiration? Giardia lamblia The viral protease found in HIV is essential for ________ of viral proteins in their active forms CLEAVAGE If 100% of the DNA contents of a transducing bacteriophage were DNA from the host chromosome what would happen when the bacteriophage infected a new bacterial cell? , No more bacteriophage would be synthesized as there is no bacteriophage genome available to direct synthesis Most pathogenicity island genes were acquired by ___________ transmission horizontal What type of bacteriophage infection results in immediate death of a host cell? Lytic After budding of new influenza virions the host cell , Is destroyed Why is perianal itching significant in the life cycle of pinworms? Eggs are trapped under fingernails and transferred to new hosts HPV virions are assembled In the nucleus Which of the following is NOT an argument for the consideration of the microbiome as a separate organ system? A human microbiome is inherited from the mother and father How do filamentous fungi grow in length? Their hyphae undergo mitosis without cell division An enveloped virus contains its envelope from The host cell The group of organisms that includes ciliates.. dinoflagellates.. and apicomplexans is known as Alveolates A single celled eukaryotic microbe proliferating by mitosis is undergoing ________ reproduction asexual Which of the following would not be a good organism choice for a vaccine delivery system? Staphylococcus aureus A free living soil ameba may contaminate contact lense solutions and cause amebic keratitis. What is the genus name of one common causative agent of amebic keratitis? Acanthamoeba On an evolutionary timeline which of the following organisms appeared last? Plants When comparing sexual reproduction to asexual reproduction.. the advantage of sexual reproduction is that it Increases genetic diversity which may be useful in a changing environment Fecal transplants can be used to treat ulcerative colitis by (Clostridium difficile) A big reason as to why HIV thus far cannot be cured is that it Contains integrase How do naturally occurring Staphylococcus strains inhibit the growth of pathogenic strains? Producing short-chain fatty acids Why is it frequently more difficult to treat fungal infections in humans than it is to treat bacterial infections? The cells found in fungi and humans are more similar than cells of bacteria and humans Shiga toxin polypeptide B binds to surface gangliosides on target cells. If the gangliosides were removed Polypeptide B would not be able to bind How is HPV able to keep its genome so small? Overlapping reading frames The presence of ______ is essential for preventing respiratory infections The mucociliary escalator Which was developed first? Phage therapy One drug target for antifungals is the membrane lipid Ergosterol Organized high density communities of cells that embed themselves in self made exopolymer matrices are called (biofilms) In addition to digested food where do carbohydrates come from in the large intestine? Mucous secretions What type of HPV can be eliminated from the body by the host immune system? Nononcogenic HPV Examine the figure below. Which toll like receptor is activated specifically by the Gram-positive organisms? TLR 2 Which of the following is not an accurate description for epithelial cells? Symmetrical Descriptions of epithelial cells: interconnected, glycoprotein covered, held together by tight junctions Examine the figure below. Which viral classification group would be the most NEGATIVELY affected by antiviral reverse transcriptase inhibitors? GROUP VI - Single Stranded RNA In the image below the pathogen uses the actin-myosin motor To enter the host cell Why do the residents of our normal microbiota not regularly invade other tissues of the body? They have not evolved the ability The presence of a core set of genomes is most important for a healthy (microbiome) All of the following are endotoxins EXCEPT: Lipopolysaccharides Examples of endotoxins: superantigens, AB toxins, plasma membrane disruption toxins Organisms such as Shigella and Listeria are able to move from cell to cell without being detected by the host immune system. They do this through the production of An actin tail that propels them from cell to cell An infectious particle with an RNA genome and no capsid is known as a (viroid) Which of the following once colonized 80% of individuals in the United States and now only colonizes 10%? Helicobacter pylori Sequestered body sites tend to be (sterile) Which of the following facts supports the argument that viruses are living? Some living pathogenic bacteria contain degenerate genomes and rely significantly on a host Which of the following statements is FALSE Protease endotoxins build proteins Colonization of the stomach requires the ability to withstand ________ conditions acidic Where are microbial metabolic end-products found in the body? Everywhere Culturing viruses is difficult because viruses Must be grown inside a living cell What type of HPV causes cancer? Some types of latent HPV Which of the following is/are used to study host-microbiota relationships in the laboratory? Gnotobiotic animals Which of the following statements regarding the influenza virus is FALSE? The influenza genome is very tiny to allow the generation of as many virions as possible Fungi obtain nutrition by Secreting digestive enzymes and absorb broken-down molecules Examine the figure shown below. Which viral classification group(s) must package a viral RNA-dependent RNA polymerase? GROUP V and III Lipopolysaccharides flagellin, and double stranded DNA are microbe-associated molecular patterns recognized by , Pattern recognition receptors Why must the genome of HPV enter the nucleus for replication? The DNA genome of HPV can only be replicated in the nucleus where host DNA polymerase is found Genomic islands have all of the following features EXCEPT They do not need toxins or secretion systems In viruses such as influenza the ability to undergo a major genetic alteration is called antigenic Shift