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MicrobiologyFill in the Blank

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When prokaryotes live as interacting communities in which one population benefits to the harm of the other, the type of symbiosis is called ________.


The domain ________ does not include prokaryotes.


Pathogenic bacteria that are part of the transient microbiota can sometimes be eliminated by ________ therapy.


Nitrogen-fixing bacteria provide other organisms with usable nitrogen in the form of ________.


Rickettsias are ________ intracellular bacteria.


The species ________, which belongs to Epsilonproteobacteria, causes peptic ulcers of the stomach and duodenum.


The genus Salmonella belongs to the class ________ and includes pathogens that cause salmonellosis and typhoid fever.


The bacterium that causes syphilis is called ________.


Bacteria in the genus Rhodospirillum that use hydrogen for oxidation and fix nitrogen are ________ bacteria.


Streptococcus is the ________ of bacteria that is responsible for many human diseases.


One species of Streptococcus, S. pyogenes, is a classified as a ________ pathogen due to the characteristic production of pus in infections it causes.


Propionibacterium belongs to ________ G+C gram-positive bacteria. One of its species is used in the food industry and another causes acne.


The length of the branches of the evolutionary tree characterizes the evolutionary ________ between organisms.


The deeply branching bacteria are thought to be the form of life closest to the last universal ________ ________.


Many of the deeply branching bacteria are aquatic and hyperthermophilic, found near underwater volcanoes and thermal ocean ________.


The deeply branching bacterium Deinococcus radiodurans is able to survive exposure to high doses of ________.


________ is a genus of Archaea. Its optimal environmental temperature ranges from 70 °C to 80 °C, and its optimal pH is 2–3. It oxidizes sulfur and produces sulfuric acid.


________ was once thought to be the cause of periodontal disease, but, more recently, the causal relationship between this archaean and the disease was not confirmed.

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