7. Prokaryotes do not have
A. cell walls. B. flagella. C. a nuclear membrane.
D. specific shapes. E. genetic information.
8. Nucleoids are associated with
1. genetic information. 2. prokaryotes. 3. eukaryotes.
9. Which of the following are eukaryotes?
1. Algae 2. Viruses 3. Bacteria
4. Prions 5. Protozoa
10. The person best known for his microscopy of microorganisms is
A. Antony van Leeuwenhoek.
B. Louis Pasteur.
C. John Tyndall.
D. Ferdinand Cohn.
1. The American Society of Microbiology is preparing a "Microbe-Free" banquet to emphasize the importance of microorganisms in the diet. What foods would not be on the menu if microorganisms were not available for our use?
2. If you were asked to nominate one of the individuals mentioned in this chapter for the Nobel Prize, who would it be? Make a statement supporting your choice.
1. An early microbiologist, who was inclined to accept the theory of spontaneous generation, criticized Pasteur's experiments (see figure 1.2). He claimed that a few spontaneously generated bacteria would be present in the boiled and cooled broth but shaking the broth was necessary to stimulate these few to start dividing. Pasteur had not included this step, and bacteria had not started dividing until the flask was tipped and the broth agitated. Does this microbiologist have a valid criticism? What kind of experiment would check this possibility?
2. A microbiologist obtained two pure isolated biological samples: one of a virus, and the other of a viroid. Unfortunately, the labels had been lost from the two samples. The microbiologist felt she could distinguish the two by analyzing for the presence or absence of a single chemical element. What element would she search for and why?
3. Chlamydias and rickettsias were once classified as viruses because of their small size and obligate intracellular growth requirement. What techniques can be used to show that they are really bacteria?
4. Why are the spores of Bacillus anthracis such an effective agent of bioterrorism?
5. Why do most "new" infectious diseases seem to arise in the United States (see figure 1.3)?
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