8. Organisms that do not require oxygen for growth but grow better in its presence are called a. facultative anaerobes b. microaerophilies c. aerotolerant d. anoxygenic 9. Organisms that ignore oxygen and grow equally well in its presence or absence are called a. facultative anaerobes b. microaerophilies c. aerotolerant d. anoxygenic 10. Organisms that are damaged by the normal atmospheric level of oxygen (20%) but require oxygen at levels of 2-10% for growth are called a. facultative anaerobes b. microaerophilies c. aerotolerant d. anoxygenic 11. One of the major advantages of a continuous culture system is that the cells can be maintained in the exponential growth phase for extended periods of time. ! (True) 12. When a microorganism is placed in a(n) ______ solution, water will enter into the cell and cause it to burst unless something is done to prevent this. a. hypotonic b. isotonic c. hypertonic d. osmotonic 13. The membranes of psychrophilic bacteria have relatively high levels of ______ fatty acids, which allow them to remain semi-fluid at cold temperatures. a. saturated b. unsaturated c. sterol d. aromatic 14. Quorium sensing a. is a phenomenon in which bacteria monitor their own population density b. depends on the sensing of signal molecules called autoinducers c. plays an important role in formation of biofilms by Pseudomonas aeruginosa d. all of the above 15. The most common types of autoinducers in gram-negative bacteria are acyl homoserine lactones ! (True) 16. DNA of thermophiles is stabilized by binding of special histone proteins ! (True)
Microbiology Tutorial on 16/03/2010
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