Commensalism is best described as
A) an unsuccessful microbial invasion due to the presence of preexisting microbes.
B) a relationship between two organisms where only one member benefits and the other is unharmed.
C) a relationship between two organisms where both members benefit.
D) a relationship in which a microorganism causes disease.
E) a source of contamination.
Answer: B
Microbiology
- Which of the following pairs is not correctly matched?
- Mycoplasmas differ from other bacteria because they
- All of the following are motile; which does not have flagella?
- What should you do if you suspect a patient has tuberculosis?
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- Which one of the following does not belong with the others?
- Which of the following pairs is mismatched?
- You have isolated an aerobic gram-positive, endospore-forming bacterium that grows wells on nutrient agar. To which of the following groups does it most likely belong?
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- You have isolated a prokaryotic cell. The first step in identification is a(n)
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- Borrelia is classified as a spirochete because it
- You have isolated a gram-positive rod. What should you do next?
- Salmonella, Shigella, Yersinia, and Serratia are all
- All of the following are gram-positive. Which does not belong with the others?
- Streptomyces differs from Actinomyces because Streptomyces
- Which of the following is the best reason to classify Streptococcus in the Lactobacillales?
- The nonsulfur photosynthetic bacteria use organic compounds as
- Both Beggiatoa and the purple sulfur bacteria use H 2S. These bacteria differ because Beggiatoa
- The bacteria responsible for more infections and more different kinds of infections are
- Which one of the following does not belong with the others?
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- All of the following are true about the causative agent of Rocky Mountain spotted fever except