MICROBIO 242 Midterm Exam Questions ANSWERS

MICROBIO 242 Midterm Exam Questions ANSWERS 1. Which of the following is ‘not’ a microscopic organism that Leewenhook was able to observe under the microscope he constructed in 1674? a. Algae b. Bacteria c. Archaea d. Viruses e. Small multicellular animals 2. Which of the following is INCORRECT regarding Archaea? a. They are known as extremophiles b. They have external features called hami c. They are grouped in the domain eukarya d. They are unicellular and lack nuclei e. None of the above 3. What is the name for sphere-shaped bacterial cells? a. Spirillium b. Bacillus c. Coccus d. Pleomorphic e. Vibrio 4. Where do you find genetic material in a prokaryotic cell? a. Nucleoid b. Vesicles c. Nucleus d. Inclusions e. Golgi Apparatus 5. Which of the following statements is INCORRECT regarding glycocalyces? a. Glycocalyces are gelatinous, sticky substances surrounding a cell. b. An example of this structure are capsules. c. They are made of a thick peptidoglycan layer. d. Glycocalyces help with protecting the cell and attachment to surfaces. e. They make up biofilms. 6. What is the name for flagella covering the perimeter of the cell? a. Antitrichous b. Peritrichous c. Lophotrichous d. Monotrichous e. Multitrichous 7. What is the name of the structure that transfers genetic material between bacterial cells? a. Cilia b. Axial Filament c. Fimbriae d. Conjugation Pili e. Hami 8. The term used to describe a disease-causing microorganism is a. Microbe b. Bacterium c. Virus d. Pathogen e. Infection 9. If a nursing student observed a typical eukaryotic cell, what would they find inside? a. Nucleolus b. Lysosome c. Mitochondria d. All of the above e. A and C 10. Cellular organelles and viruses are very small compared to prokaryotic and eukaryotic cells and are generally measured in a. Nanometers b. Millimeters c. Micrometers d. Centimeters e. Decimeters 11. Bacteria form endospores under which circumstances? a. Before conjugation b. Right after cell division c. In darkness d. While infecting a host e. Under unfavorable environmental conditions 12. If a microbiology lab technician left safranin out of the Gram stain procedure, what would be the result? a. All cells would be purple. b. Gram-positive cells would be purple, and Gram-negative cells would be colorless. c. All cells would be pink. d. Gram-positive cells would be pink, and Gram-negative cells would be purple. e. Gram-positive cells would be colorless, and Gram-negative cells would be pink. 13. A(n) organism is one that requires oxygen for growth and cannot function without it. a. Anaerobic b. Facultative Anaerobic c. Aerotolerant d. Obligate Aerobic e. Both aerotolerant and anaerobic 14. During the of growth, new cells are being produced at the same rate as the other cells are dying. a. Lag Phase b. Stationary Phase c. Log Phase d. Conjugation Phase e. Death Phase 15. All of the following are associated with smear preparation except . a. Spread culture in thin film over slide b. Place slide under UV light for 25 sec c. Air Dry d. Pass slide trough flame to fix it e. None of the above 16. The majority of human pathogens are classified as a. Thermophiles b. Barophiles c. Psychrophiles d. Acidophiles e. Mesophiles 17. What process of cellular respiration ultimately produces the most ATP? a. Glycolysis b. Electron Transport Chain c. Kreb’s Cycle d. Fermentation e. Acetyl coA 18. Anabolic reactions may be characterized as a. Exergonic b. Breaking large molecules into smaller molecules c. Forming large molecules from smaller molecules d. Hypergonic e. Producing ATP 19. What is the purpose of an enzyme in a chemical reaction? a. Stop cellular metabolic pathways b. Slow down the speed of the reaction c. Decrease activation energy d. Alter the shape of an enzyme’s activation site e. Increase activation energy 20. Which eukaryotic organism can have 2 nuclei and contractile vacuoles? a. Archae b. Protozoa c. Fungi d. Yeasts e. Plants 21. Which of the following statements about competitive inhibitors is false? a. Competitive inhibitors do not denature enzymes. b. They are structurally similar to the enzyme’s substrate. c. They bind to the enzyme’s active site. d. Their presence regulates enzyme activity. e. None of the above 22. Which Eukaryotic organism obtains nutrients by decomposing dead organisms? a. Protozoa b. Bacteria c. Fungi d. Plants e. None of the above 23. Sister chromatids separate and move toward the poles of the cell during of mitosis. a. Telophase b. Interphase c. Prophase d. Anaphase e. Metaphase 24. The extracellular state of a virus is called a . a. Viriae b. Vector c. Viral d. Virion e. Virus 25. Unknown (Pretty sure this one was about AESAR order) 26. Which viral structure is acquired from the host cell during viral replication or release? a. Head b. Capsomere c. Envelope d. Capsid e. Mitochondria 27. Pyruvic acid is a product of . a. Krebs Cycle b. Fermentation c. Glycolysis d. Electron Transport Chain e. Beta Oxidation 28. Which of the following is the most appropriate pairing of microbe and biosafety level? a. E, coli, BSL-3 b. Anthrax, BSL-1 c. Ebola, BSL-2 d. Methicillin-Resistant staphylococcus aureus (MRSA), BSL-2 e. Tuberculosis, BSL-1 29. A very large zone of inhibition in the Kirby-Bauer test means . a. Organism is resistant to the microbe. b. Organism is susceptible to the antibiotic c. Antibiotic has no effect d. Adverse reaction to the antibiotic e. Organism is intermediate 30. Why are endospores used to measure the effectiveness of autoclave sterilization? a. Endospores are easy to store. b. Endospores are very simple structures. c. Endospores are very hard to kill. d. Endospores are composed of all the molecules found in living cells. e. Endospores do not change the color of the medium. 31. The major disadvantage to using broad-spectrum antibiotics is that they a. Destroy normal microbiota b. Are easily activated by the host c. Are extremely toxic d. Target host cells e. None of the above 32. Why are cell membranes a good target for antimicrobial drugs? a. The drug gets trapped in the NAG/NAM subunits. b. These barriers allow genetic information to enter neighboring cells. c. The cell wall becomes rigid and allows all molecules to enter freely. d. Rupturing the cell membrane causes the cellular contents to leak out, eventually killing the cell. e. None of the above. 33. Which is not a factor that affects the efficacy of antimicrobial methods? a. Site to be treated b. Relative susceptibilities c. Temperature d. Organic material e. None of the above 34. Why does milk go bad after pasteurization? a. The milk proteins become denatured b. Pastuerization kills all microbes c. The cows that produce the milk were unhealthy d. Pasteurization only heats milk enough to reduce the number of pathogens 35.