Nester Microbiology Chapter 4: Dynamics of Prokaryotic Growth

2. Question 1 A method that counts only live microbes is the A. pure culture method. B. plate count method. C. cell counting method. D. turbidity method. E. none of the above.

3. Question 2 To develop a pure culture from a mixed culture, a microbiologist may use the A. pour plate method. B. streak plate method. C. membrane filtration method. D. all of the above. E. none of the above.

4. Question 3 The problem with using gelatin as a solidifying agent for microbiological media is that A. many organisms can degrade gelatin. B. gelatin may not remain solid at temperatures required for a microbe's growth. C. gelatin is not stable during sterilization procedures. D. a and b. E. all of the above.

5. Question 4 A microorganism isolated from the Antarctic would most likely be A. a mesophile. B. facultative. C. a psychrophile. D. extremophilic. E. none of the above.

6. Question 5 A microorganism that can utilize oxygen when it is available but also can grow without oxygen is A. microaerophilic. B. aerobic. C. an aerotolerant anaerobe. D. a facultative anaerobe. E. none of the above.

7. Question 6 Enzyme(s) that can help an organism survive the toxic effects of oxygen is (are): A. catalase. B. peroxidase. C. superoxide dismutase. D. all of the above. E. a and c.

8. Question 7 Organisms that require organic compounds for energy and a carbon source are called A. chemoautotrophs. B. organoheterotrophs. C. mesotrophs. D. psychrotrophs. E. none of the above.

9. Question 8 Strict anaerobes contain A. catalase. B. superoxide dismutase. C. dioxidase. D. a and b. E. none of the above.

10. Question 9 Which of the following is NOT a true statement: A. Bacteria growing in log phase would be the least affected by antibiotics. B. The generation time of bacteria may vary from species to species. C. Most bacteria divide by binary fission, producing two daughter cells. D. Secondary metabolites are normally produced during late log phase. E. In the lag phase, cells increase the number of ribosomes they contain.

11. Question 10 A growth medium that can discriminate between two different bacterial species based on an observed change in the media is termed A. a defined medium. B. a differential medium. C. a complex medium. D. selective. E. fastidious.

12. Question 11 When cell number increases exponentially, the phase of the culture cycle is termed A. lag. B. log. C. stationary. D. death. E. none of the above.

13. Question 12 The growth phase when cells are adapting to new growth conditions is termed A. lag. B. log. C. stationary. D. death. E. none of the above.

14. Question 13 Differential media is used to A. enrich for one specific organism. B. distinguish one organism from other organisms. C. isolate a specific organism or group of organisms. D. only limit growth of one specific organism. E. none of the above.

15. Question 14 A chemostat allows for A. certain species of bacteria to be selected. B. certain species of bacteria to be enriched. C. bacteria to be maintained in continuous exponential growth. D. the maintenance of bacteria for future generations. E. none of the above.

16. Question 15 A mixture of organisms is in a pool of seawater. Which organism will have a growth advantage as the water evaporates? A. neurophiles. B. aerotolerant anaerobes. C. mesophiles. D. osmotolerant prokaryotes. E. psychrophiles.

17. Question 16 The Most Probable Number (MPN) method of determining cell numbers is based on A. serial dilutions. B. turbidity. C. membrane filtration. D. direct microscopic count. E. cell-counting chamber.

18. Question 17 During which phase of culture growth are cells not actively dividing? A. stationary. B. lag. C. death. D. all of the above. E. a and c.

19. Question 18 Which of the following statements is NOT true concerning biofilms? A. They are important in a number of bacterial infections. B. They increase effectiveness of disinfectants. C. They are held together by glycocalyx. D. They are mixtures of different microorganisms. E. They have cell to cell communication between microorganisms.

20. Question 19 A pure bacterial culture maintained under completely anaerobic conditions accidentally develops a leak, letting oxygen into the chamber. Surprisingly, the bacteria continue to grow. It is very likely to conclude that the bacteria are: A. Thermophiles. B. Halophiles. C. Aerobic. D. Facultative anaerobes. E. Microaerophilic.

21. Question 20 A scientist wishes to monitor the growth and health of a bacterial culture by measuring ATP production. Which of the following would she most likely use to measure ATP? A. A pH meter. B. Luciferase. C. Blood culture. D. An inverted tube culture. E. A visible light spectrophotometer.

22. Question 21 Tomato sauce has a pH of 5. A scientist isolates several types of bacteria that cause spoilage to the tomato sauce. Which of the growth conditions should be used to maintain these bacteria in culture? A. Acidophilic. B. Alkaliphilic. C. Basophilic. D. Neutrophilic. E. Microaerophilic.

23. Question 22 Bile is added to some media to encourage the growth of certain medically important bacteria while inhibiting the growth of others. Which of the following properties is bile adding to the media? A. Differential properties. B. Anaerobic properties. C. Selective properties. D. Reducing properties. E. Alkaline.

24. Question 23 A researcher is maintaining a liquid culture of bacteria at exponential growth. The pump providing nutrients to the culture breaks down over the weekend, allowing culture to run out of nutrients. It is very likely that upon return to the lab the researcher will find the culture in which of the following stages of growth? A. Continuous. B. Log. C. Lag. D. Medium. E. Stationary.