Micro Exam 2 (2) PDF
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This document contains a microbiology exam covering various aspects of disinfectants, sterilization, and microbial control methods. It features multiple-choice questions and covers topics such as heat treatments and chemical agents used for microbial control.
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Chapter 7 Quiz In hospitals, the presence of ___________ in blood, vomitus, and feces influences the selection of disinfectants. treatment drugs odors inorganic matter organic matter Most disinfectants work better in ___________ solutions. cold acidic warm organic Commercial sterilization is a li...
Chapter 7 Quiz In hospitals, the presence of ___________ in blood, vomitus, and feces influences the selection of disinfectants. treatment drugs odors inorganic matter organic matter Most disinfectants work better in ___________ solutions. cold acidic warm organic Commercial sterilization is a limited heat treatment to destroy Staphylococcus aureus Clostridium botulinum endospore Clostridium tetani Streptococcus pyogenes Heat-resistant bacteria that survive pasteurization are anaerobic pathogenic thermoduric fermented Which one of the following damages the plasma membrane of a cell and was first used by Lister to control surgical infections? Phenol Ethylene oxide Ozone Halogens Which treatment is intended to lower microbial counts on eating and drinking utensils to save public health levels? Sanitization Sterilization Pasteurization Antisepsis Which of the following best describes the rate of microbial death when treated with antimicrobial chemicals? Cells in a population die at a constant rate. The rate varies, depending on the species Some cells are never killed All cells in a population die at once The recommended optimum concentration of ethanol to use as a biocide is 70%. 50%. 10%. 100%. Which of the following have little value as antiseptic, but are used to mechanically remove microbes? Chlorines Phenolics Soaps Quats To sterilize heat-sensitive solutions such a culture media, enzymes, and vaccines, one should use dry heat pasteurization filtration an autoclave Chapter 7 homework Which of the following treatments is the most effective for controlling microbial growth? 72°C for 15 seconds None of the answers is correct. 140°C for 4 seconds They are equivalent treatments. 63°C for 30 minutes The antimicrobial activity of chlorine is due to which of the following? the formation of hydrochloric acid the formation of ozone the formation of hypochlorous acid disruption of the plasma membrane the formation of a hypochlorite ion Antimicrobial agents that damage nucleic acids also affect endospores. the cell membrane. the viral envelope. protein synthesis. the cell wall. Which of the following chemical agents is used for sterilization? alcohol soap phenolics chlorine ethylene oxide Which of the following is used for microbial control in fresh fruits and vegetables? electron beams microwaves gamma rays X rays ultraviolet light Which of the following methods is used to preserve food by slowing the metabolic processes of foodborne microbes? freezing pasteurization nonionizing radiation lyophilization ionizing radiation All of the following substances are used to preserve foods EXCEPT sodium nitrite. calcium propionate. biguanides. potassium sorbate. nisin. Which of the following could be used to sterilize plastic Petri plates in a plastic wrapper? microwaves sunlight autoclave ultraviolet radiation gamma radiation Which one of the following is most resistant to chemical biocides? gram-positive bacteria gram-negative bacteria viruses with lipid envelopes mycobacteria protozoan cysts Bone and tendons for transplant are decontaminated by supercritical fluids. glutaraldehyde. peroxygens. ethylene oxide. plasma sterilization. All of the following are methods of food preservation EXCEPT high pressure. microwaves. ionizing radiation. desiccation. osmotic pressure Which of the following substances is used for surgical hand scrubs? chlorine bleach soap phenol glutaraldehyde chlorhexidine Which of the following pairs of terms is mismatched? virucide — inactivates viruses fungicide — kills yeasts and molds germicide — kills microbes bacteriostatic — kills vegetative bacterial cells sterilant — destroys all living microorganisms Which of the following does NOT achieve sterilization? dry heat autoclave supercritical fluids pasteurization ethylene oxide Which of the following pairs is mismatched? H2O2 — open wounds Ag — wound dressings alcohols — open wounds CuSO4 — algicide organic acids — food preservation An agent used to reduce the number of bacteria on a toilet would most accurately be called a(n) virucide. fungicide. disinfectant. antiseptic. aseptic. The preservation of beef jerky from microbial growth relies on which method of microbial control? desiccation filtration lyophilization ionizing radiation supercritical CO2 Which of the following is a limitation of the autoclave? It cannot be used with heat-labile materials. It cannot inactivate viruses. It requires an excessively long time to achieve sterilization. It cannot be used with glassware. It cannot kill endospores. Which of the following regarding antimicrobial control agents is FALSE? Some agents kill by denaturing microbial cell proteins. Some agents affect microbial cell membranes by dissolving lipids. Contaminating organic debris such as blood or sputum decrease effectiveness. Alcohols effectively inactivate nonenveloped viruses by attacking lipids. Silver is used for treating antibiotic-resistant bacteria. Figure 7.2 Assume 109 E. coli cells/ml are in a flask. Which graph in Figure 7.2 best depicts the effect of placing the culture in an autoclave for 15 minutes at time x? d a b e c Chapter 8 quiz DNA polymerase adds new nucleotides specifically and only to the ________ end of the growing DNA strand. 4' 2' 3' 5' In DNA replication, the newly added nucleotideis joined to the growing DNA strand by DNA ligase DNA gyrase DNA polymerase RNA polymerase Single-stranded RNA molecules that inhibit protein production in eukaryotic cells are known as rRNA tRNA mRNA microRNAs (miRNAs) Mutations in which one or a few nucleotide pairs are deleted or inserted in the DNA are called base-pair mutations frameshift mutation nonsense mutations point mutations Which molecules recognize specific codons and transport amino acids to translate those specific codons? DNA mRNA tRNA rRNA Transformation is the transfer of DNA from a donor to a recipient cell via _________. sexual reproduction. naked DNA in solution. a bacteriophage. crossing over What carries the coded information for making specific proteins from DNA to ribosomes? tRNA RNA polymerase mRNA rRNA Inhibition of the metabolism of alternative carbon sources by glucose is called corepression induction epigenetic control catabolite repression The process in which bacterial DNA is transferred from a donor cell to a recipient cell inside a bacteriophage is called crossing over conjugation transduction. Transformation Thymine dimers can be repaired by light-repair enzymes known as ligases gyrases methylases photolyases Chapter 8 Homework Genetic change in bacteria can be brought about by conjugation. transformation. All of the answers are correct. transduction. mutation. Which of the following enzymes and their function are MISMATCHED? DNA ligase—joins pieces of DNA together RNA polymerase—makes DNA DNA polymerase—synthesizes DNA and proofreads NA helicase—unwinds two strands of DNA Which of the following is NOT a product of transcription? a new strand of DNA tRNA rRNA None of the answers are correct; all of these are products of transcription. mRNA Which one of the following is a method of vertical gene transfer? Conjugation Transduction Transformation Cell division The Ames test is used __________. to determine the carbohydrate requirements of gram-negative bacteria to determine if bacteria develop cancer to determine if Salmonella can use the amino acid histidine to determine if a chemical is mutagenic and possibly carcinogenic An enzyme that copies DNA to make a molecule of RNA is transposase. DNA ligase. RNA polymerase. DNA polymerase. DNA helicase. Which of the following statements regarding the flow of genetic information is false? Ribosomes function as factories that coordinate the functioning of mRNA and tRNA. Transcription occurs in the cytoplasm of eukaryotic cells. Polypeptides form proteins that determine the appearance and function of the cell and organism. Eukaryotic mRNA is processed in several ways before export out of the nucleus. Protein synthesis in eukaryotes is similar to the process in prokaryotes in that both eukaryotes and prokaryotes require snRNPS. use methionine as the "start" amino acid. have introns. use codons to determine polypeptide sequences. have exons. Both transcription and DNA replication involve __________. synthesis of molecules containing the sugar deoxyribose synthesis using a DNA template synthesis of molecules containing the nitrogenous base thymine formation of molecules containing the same number of nucleotides as the parent chromosome Which of the following statements is FALSE? The leading strand of DNA is made continuously. DNA polymerase joins nucleotides in one direction (5' to 3') only. DNA replication proceeds in only one direction around the bacterial chromosome. The lagging strand of DNA is started by an RNA primer. Multiple replication forks are possible on a bacterial chromosome. Which of these statements is NOT true of translation? Each amino acid is coded for by a single codon. Three different nonsense codons code for termination of protein synthesis. A single mRNA may have several ribosomes attached. The "language" of nucleotides is changed to the "language" of amino acids. In the lac operon of E. coli, __________. the structural genes cease to be transcribed if allolactose binds to the repressor the gene for beta-galactosidase is regulated independently of a gene for lactose uptake by the cell the repressor protein binds to the operator in the absence of lactose the operon consists entirely of three structural genes for lactose utilization Which of the following statements in NOT true of plasmids? They can be transferred between bacteria during conjugation. They are essential for survival of the organism in most situations. They may encode genes that enhance the pathogenicity of an organism. They may contain antibiotic resistance genes. Conjugation differs from reproduction because conjugation copies RNA to make DNA. transcribes DNA to RNA. transfers DNA vertically, to new cells. transfers DNA horizontally, to nearby cells without those cells undergoing replication. replicates DNA. Using the genetic code below, what protein sequence does the RNA sequence CUAGCUCGAUAUCUC code for? Val - Arg - Ala - Phe – Stop Asp - Ala - Arg - Ile- Leu Leu - Ala - Arg - Tyr - Leu Leu - Gly - Tyr - Ala — Leu The antibiotic kasugamycin blocks binding of bacterial tRNA that carries formylmethionine to a ribosome. From this information, you can conclude that kasugamycin prevents __________. conjugation gene transcription DNA replication protein synthesis To begin transcription, the RNA polymerase binds a region on DNA known as the __________. terminator promoter operator starting sequence If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy? the tertiary structure of the protein the primary structure of the protein The answer cannot be determined based on the information provided. the secondary structure of the protein the quaternary structure of the protein Table 8.2 Codon on mRNA and corresponding amino acid UUA leucine UAA nonsense GCA alanine AAU asparagine AAG lysine UGC cysteine UCG, GUU valine serine UCU Refer to Table 8.2. If the sequence of amino acids encoded by a strand of DNA is serine-alanine-lysine-leucine, what is the order of bases in the sense strand of DNA? 3' UGUGCAAAGUUA 5' TGTGCTTTCTTA 3' TCTCGTTTGTTA 3' AGACGTTTCAAT 5' AGAGCTTTGAAT Which of the following options most accurately lists the sequence of events in translation? codon recognition → peptide bond formation → termination → translocation codon recognition → translocation → peptide bond formation → termination codon recognition → peptide bond formation → translocation → termination peptide bond formation → codon recognition → translocation → terminate Chapter 11 Quiz The most common infectious genus in the world which only lives inside the cells of insects is Brucella Coxiella Wolbachia Bartonella The phylogenetic relationship among proteobacteria is based on ________ studies. rRNA DNA mRNA tRNA The diseases tetanus, botulism, and gas gangrene are associated with the genus Enterococcus. Clostridium. Staphylococcus. Bacillus. Unlike cyanobacteria, green sulfur and nonsulfur bacteria lack a cell wall. are Gram-positive. conduct anoxygenic photosynthesis. are heterotrophic. The high G + C Gram-positive bacteria belong to the phylum Bacteroidetes. Chlorobi. Actinobacteria. Firmicutes. Rickettsias differ from chlamydias in that only rickettsias are intracellular parasites form spores are Gram negative require an arthropod for transmission Which of the following causes syphilis? Leptospira interrogans Treponema pallidum Chlamydia trachomatis Borrelia burgdorferi Alphaproteobacteria often have stalklike or budlike protrusions known as elementary bodies myxospores prosthecae axial filaments The enzymes that fix nitrogen gas into ammonium in cyanobacteria are located in heterocysts. mitochondria. magnetosomes. chloroplasts. Elementary bodies are found in the phylum Chloroflexi. Planctomycetes. Bacteroidetes. Chlamydiae. Chapter 11 Homework Which of the following bacteria are responsible for more infections and more different kinds of infections? Staphylococcus Pseudomonas Neisseria Salmonella Streptococcus Which of the following is NOT an enteric? Enterobacter Salmonella Escherichia Shigella Campylobacter All of the following bacteria are gram-positive. Which does NOT belong with the others? Corynebacterium Mycobacterium Gardnerella Actinomyces Listeria Which of the following lacks a cell wall? Mycobacterium Borrelia Mycoplasma Nocardia Clostridium Borrelia is classified as a spirochete because it is transmitted by ticks. is a rod. is a pathogen. is aerobic. possesses an axial filament. A primary difference between cyanobacteria and purple and green phototrophic bacteria is cell type. cell wall type. energy source. color. electron donor for CO2 reduction. Which of the following is NOT a characteristic of Neisseria? oxidase-positive cocci requires X and V factors Some species are human pathogens. gram-negative Which of the following bacteria is gram-negative? Staphylococcus Mycobacterium Treponema Bacillus Corynebacterium Which of the following are found primarily in the intestines of humans? gram-negative aerobic rods and cocci endospore-forming rods gram-positive cocci facultatively anaerobic gram-negative rods aerobic, helical bacteria Both Beggiatoa and the purple sulfur bacteria use H2S. These bacteria differ in that Beggiatoa belongs to the gammaproteobacteria. is a heterotroph. uses H2S for an energy source. uses H2S for a carbon source. uses light energy. Which one of the following bacteria does NOT belong with the others? Escherichia Lactobacillus Bacillus Staphylococcus Streptococcus Rickettsias differ from chlamydias in that rickettsia are intracellular parasites. form elementary bodies. are enterics. are gram-negative. require an arthropod for transmission. Escherichia coli belongs to the spirochetes. proteobacteria. green sulfur bacteria. actinomycetes. gram-positive bacteria. Which of the following do you expect to be MOST resistant to high temperatures? Neisseria gonorrhoeae Streptococcocus pyogenes Bacillus subtilis Staphylococcus aureus Eschericia coli Staphylococcus and Streptococcus can be easily differentiated in a laboratory by which one of the following? glucose fermentation Gram stain reaction growth in high salt concentrations ability to cause disease cell shape Requirements for X and V factors are used to identify Escherichia. Haemophilus. Neisseria. Pseudomonas. Staphylococcus. You have isolated a prokaryotic cell. The first step in identification is a(n) flagella stain. Gram stain. DNA fingerprint. lactose fermentation test. endospore stain. Which of the following statements about the causative agent of Rocky Mountain spotted fever is FALSE? It is an intracellular parasite. It is gram-negative. It is in the genus Rickettsia. It is found in soil and water. It is transmitted by ticks. Which of the following bacteria is gram-positive? Streptococcus Salmonella Rickettsia Pseudomonas Bacteroides Which of the following is NOT a characteristic of spirochetes? easily observed with brightfield microscopy helical shape gram-negative found in the human oral cavity possess an axial filament Chapter 12 Quiz Which of the following statements about helminths is FALSE? All are parasitic They are heterotrophic The are multicellular They have eukaryotic cells Which is the correct order of events for production of sexual spores? meiosis, plasmogamy, karyogamy karyogamy, plasmogamy, meiosis plasmogamy, karyogamy, meiosis karyogamy, meiosis, plasmogamy Tapeworms obtain nutrients from a host's muscle blood intestines liver Arthropods that carry pathogenic microorganisms are called vectors. reservoirs. fomites. vehicles. Paralytic shellfish poisoning is caused by dinoflagellates that secrete a neurotoxin known as exotoxin endotoxin saxitoxin. aflatoxin The parasite that causes African sleeping sickness is Toxoplasma gondii. Trypanosoma brucei. Plasmodium vivax. Amoeba proteus. Which of the following is the vector of Lyme disease? mite tick louse mosquito In which phylum has sexual reproduction NOT been observed? Ascomycota Microsporidia Basidiomycota cota Zygomycota Unicellular algae with complex cell walls made of pectin and a layer of silica are green algae. dinoflagellates diatoms. red algae The feeding or growing stage of a protozoan is called the merozoite trophozoite sporozoite hypnozoite Chapter 12 Homework Which of the following pairs are mismatched? 1. arthroconidium — formed by fragmentation 2. sporangiospore — formed within hyphae 3. conidiospore — formed in a chain 4. blastoconidium — formed from a bud 5. chlamydoconidium — formed in a sac 2 and 3 2 and 5 1 and 2 3 and 4 4 and 5 Which of the following organisms is photoautotrophic protozoan? plasmodial slime mold oomycote Euglena cellular slime mold Phytophthora Table 12.1 1-Arthroconidium 5-Chlamydoconidium 2-Ascospore 6-Conidiospore 3-Basidiospore 7-Sporangiospore 4-Blastoconidium 8-Zygospore In Table 12.1, which of these spores are characteristic of Penicillium? 1 and 4 3 and 4 2 and 6 4 and 6 1 and 2 Sexual reproduction in Basidiomycota results in the production of conidiospores. endospores. ascospores. basidiospores. zygospores. Helminthic diseases are usually transmitted to humans by respiratory route. genitourinary route. gastrointestinal route. vectors. aerosols. The large seaweed known as kelp is classified as a member of the Deuteromycete. Chlorophyta. Rhodophyta. Phaeophyta. Chrysophyta. Which of the following arthropods does NOT transmit diseases by sucking blood from a human host? mosquitoes kissing bugs lice houseflies fleas Some fungi postpone cytokinesis, producing merozoites. trophozoites. coenocytes. schizonts. cysts. Which of the following has NOT been a basis for classification of the protozoa? ability to form a dormant stage means of locomotion habitat photosynthetic ability genetic sequences Which of the following pairs is mismatched? microsporidia — lack mitochondria Ascomycota — conidiospores Zygomycota — sporangiospores Basidiomycota — basidiospores anamorphs — lack spores The Apicomplexa are named for their apical complexes which allow them to be motile by means of multiple flagella. penetrate the cytoplasmic membranes of host cells. carry out photosynthesis. undergo schizogony. attach to surfaces. The ________ is the entire interwoven mass of one multicellular fungal organism. hyphae conidiophore pseudoplasmodium sporangium mycelium Single-celled eukaryotes lacking a cell wall are fungi. protozoa. algae. water molds. insects. Which of the following statements is FALSE? Fungal spores are used in identification of fungi. Fungi produce sexual spores. Fungal spores are highly resistant to heat and chemical agents. Fungal spores are for asexual or sexual reproduction. Fungi produce asexual spores. In the microscope, you observe multinucleated amoeboid cells with sporangia that form spores. This is a(n) tapeworm. plasmodial slime mold. ascomycete. Euglenozoa. cellular slime mold. In the malaria parasite life cycle, humans are the ________ host, while mosquitoes are the ________ host as well as the vector. definitive; intermediate intermediate; intermediate temporary; final intermediate; definitive vector; intermediate Which of the following statements regarding lichens is FALSE? Lichens are a mutualistic relationship between a fungus and a protozoan. Lichens are often the first life form to colonize rock or soil. The algal partner produces carbohydrates that are absorbed by the fungal partner. Lichens represent a mutualistic relationship between a fungus and an alga. The fungal partner provides a means of attachment and protects the algal partner from desiccation. A definitive host harbors which stage of a parasite? adult All of the answers are correct. larva miracidium cyst Which of the following is the most effective control for malaria? eliminate the intermediate host eliminate Anopheles mosquitoes treating patients vaccination None of these is an effective control. Fungal spores produced asexually within a sac-like chamber at the tip of a hypha are called conidia. sporangiospores. ascospores. basidiospores. zygospores. Chapter 13 Quiz Cell deteriorations due to viral infections are known as biosynthesis. transformations. plaques. cytopathic effects. Prion diseases can be acquired via all of the following EXCEPT contaminated surgical instruments ingestion inhalation transplanted nerve tissue Which one of the following is an example of a persistent viral infection in humans? Influenza Cold sores Shingles HIV / AIDS What is/are the most common method(s) used to identify viruses? Serological methods Observation of cytopathic effects Polymerase chain reaction (PCR) Morphology The enzymes that uses viral RNA as a template to produce complementary double-stranded DNA is. RNA-dependent RNA polymerase. DNA polymerase. DNA ligase reverse transcriptase. Viruses that infect and lyse cancer cells are called latent viruses oncogenic viruses. lysogenic viruses oncolytic viruses. ALL of the following can be used to culture animal viruses EXCEPT glucose broth embryonated eggs laboratory animals. laboratory animals Which one of the following is an example of a latent viral infection in humans? Influenza Shingles Measles HIV / AIDS Capsids are composed of protein subunits known as capsomeres. spikes. envelopes. tail fibers. Which one of the following is true regarding viruses? They multiply by binary fission. Virions contain both DNA and RNA They are not composed of cells. They are sensitive to antibiotics. Chapter 13 Homework Oncogenic viruses are lytic viruses that kill the host cell. cause acute infections. are genetically unstable. have no effect on the host cell. cause tumors to develop. Which of the following is necessary for replication of a prion? lysozyme RNA DNA polymerase DNA PrPSc The mechanism whereby an enveloped virus leaves a host cell is called budding. lysogeny. penetration. abduction. transduction. Most RNA viruses carry which of the following enzymes? reverse transcriptase RNA-dependent RNA polymerase lysozyme ATP synthase DNA-dependent DNA polymerase A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient? The virus is causing the death of the infected cells in the patient. The virus is infecting cells and then releasing only small amounts of virus. The virus is incorporating its nucleic acid with that of the patient's cells. The virus is not killing any cells in the host. The virus is slowly killing the patient's cells. A persistent infection is one in which the virus remains in equilibrium with the host without causing a disease. host cells are gradually lysed. the disease process occurs gradually over a long period. host cells are transformed. viral replication is unusually slow. The definition of lysogeny is lysis of the host cell due to a phage. when the burst time takes an unusually long time. attachment of a phage to a cell. the period during replication when virions are not present. phage DNA is incorporated into host cell DNA. A viroid is a(n) complete, infectious virus particle. infectious protein. infectious piece of RNA without a capsid. capsid without nucleic acid. provirus. Which of the following statements is NOT true of lysogeny? Prophage is inserted into the host genome. Lytic cycle may follow lysogeny. It causes lysis of host cells. It is a "silent" infection; the virus does not replicate. It can give infected pathogens the genetic information for toxin production. A virus's ability to infect an animal cell depends primarily upon the presence of receptor sites on the cell membrane. host cell's ability to phagocytize viral particles. type of viral nucleic acid. presence of pili on the host cell wall. enzymatic activity of a host cell. Viruses that utilize reverse transcriptase belong to the virus families Herpesviridae and Retroviridae. Rhabdoviridae and Herpesviridae. Herpesviridae and Poxviridae. Hepadnaviridae and Retroviridae. Retroviridae and Picornaviridae. Lysogeny can result in all of the following EXCEPT acquisition of new characteristics by the host cell. specialized transduction. immunity to reinfection by any phage. immunity to reinfection by the same phage. phage conversion. Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals? They are not composed of cells. They cause diseases similar to those caused by chemicals. They are filterable. They are chemically simple. They cannot reproduce themselves outside a host. A clear area against a confluent "lawn" of bacteria is called a plaque. rash. phage. cell lysis. pock. An infectious protein is a bacteriophage. retrovirus. papovavirus. viroid. prion. How do all viruses differ from bacteria? Viruses are obligate intracellular parasites. Viruses do not have any nucleic acid. Viruses are not composed of cells. Viruses do not reproduce. Viruses are filterable. A viral species is a group of viruses that has the same genetic information and ecological niche. cannot be defined. has the same morphology and nucleic acid. infects the same cells and cause the same disease. Which of the following statements about viral spikes is FALSE? They bind to receptors on the host cell surface. They may cause hemagglutination. They are composed of carbohydrate-protein complexes. They are used for attachment. They are found only on nonenveloped viruses. Continuous cell lines differ from primary cell lines in that continuous cell lines can be maintained through an indefinite number of generations. viruses can be grown in continuous cell lines. continuous cell lines always have to be re-isolated from animal tissues. continuous cell lines are from human embryos. continuous cell lines are derived from primary cell lines. An envelope is acquired during which of the following steps? penetration release uncoating adsorption biosynthesis