Microbiology 303 - Chapters 19-20

Methane Monooxygenase is an enzyme that can... A). Oxidize methane B). Be used in the synthesis of commercial products from methane C). Can split O2 molecules D). Can be used to oxidize xenobiotic compounds during bioremediation.

A). Oxidize methane B). Be used in the synthesis of commercial products from methane. C). Can split O2 molecules D). Can be used to oxidize xenobiotic compounds during bioremediation

Methanogens.... A). Synthesize methane B). Oxidize methane C). Require oxygen D). Are present in the human gut

A). Synthesize methane D). Are present in the human gut

The largest reservoir of methane is found... A). Trapped under permafrost and marine sediments B). in the rumen of cows and other ruminant animals C). In the atmosphere D). Trapped in volcanic rocks.

A). Trapped under permafrost and marine sediments.

Which of the following processes does denitrification contribute to? A). Agricultural fertilizer B). Acid Rain C). Ozone depletion D). Global warming

D). Global warming

Which group of organisms form the foundation of the carbon cycle as primary producers? A). Anaerobic chemolithotrophs B). Chemoheterotrophs C). Chemoorganotrophs D). Phototrophs

D). Phototrophs

The metabolic process of denitrification... A). Oxidizes N2 B). Oxidizes NO3- C). Reduces N2 D). Reduces NO3-

D). Reduces NO3-

A process where different microbial taxa work in cooperation to degrade a compound is called... A). Allotropy B). Commensalism C). Anabolism D). Syntrophy

D). Syntrophy

Which of the following forms of carbon remain following microbial degradation? A). Methane B). Fossil fuels C). Carbon dioxide D). Organic matter

A). Methane C). Carbon dioxide

What is the main form of nitrogen found on the Earth? A). N2 B). NO C). NO3- D). NH4

A). N2

Which of the following are consequences of an influx of carbon into a freshwater lake? A). Chemoorganotroph population increases B). Overall microbial diversity decreases C). Nitrification increases D). Algal blooms arise

A). Chemoorganotroph population increases B). Nitrification increases

Which of the following is a sulfide? A). H2S B). HS- C). S2- D). SO4

A). H2S B). HS- C). S2-

Frozen methane molecules... A). Are called methane hydrates B). Are oxidized by methanogens C). Are present in abundance in ocean sediments D). Has been connected to mass extinctions during earth's history

A). Are called methane hydrates C). Are present in abundance in ocean sediments. D). Has been connected to mass extinctions during earth's history

Human activities have disrupted the carbon cycle by... A). Burning carbon stored as fossil fuels or biomes, thus increasing the amount of carbon dioxide in the atmosphere. B). Decreasing the primary productivity of the oceans, resulting in increased atmospheric carbon dioxide. C). Burning methane hydrates to produce electricity. D). Acidifying the ocean, resulting in the release of large amounts of dissolved carbon dioxide into the atmosphere.

A). Burning carbon stored as fossil fuels or biomes, thus increasing the amount of carbon dioxide in the atmosphere.

When in the human gut, E. coli grows... A). At the same rate regardless of what the human host eats. B). More slowly than in lab C). In a pure culture D). At the same rate in every part of the human GI tract

B). More slowly than in lab

Nitrification and anammox both... A). Create nitrogen gas B). Oxidize ammonia C). Are aerobic processes D). Occur in soils at neutral pH

B). Oxidize ammonia

Nitrapyrin is used by farmers to... A). Enhance nitrogen fixation B). Prevent nitrification C). Prevent denitrification D). Fertilize crops

B). Prevent nitrification C). Precent dentrificaiton

The metabolic process of ammonification _________ ammonia. A). Oxidizes B). Produces C). Reduces D). Transforms

B). Produces

One important difference between the C, N, and S cycles and the P, Ca, and Si cycles is that... A). the P, Ca, and Si are NOT cycled in terrestrial environments B). the P, Ca, and Si cycles do NOT involve redox changes or gaseous forms that can alter Earth's atmospheric chemistry. C). the P, Ca, and Si cycles do NOT involve microbial activity. D). the P, Ca, and Si cycles are NOT affected by global warming or other human activity.

B). the P, Ca, and Si cycles do NOT involve redox changes or gaseous forms that can alter Earth's atmospheric chemistry.

Agricultural application of nitrogen fertilizer... A). Reduces global warming by increasing the storage of carbon dioxide in plant. B). Increases global warming by increasing microbial respiration in agricultural soils. C). Increases global warming by increasing the production of nitrous oxide (N2O) by identification in agricultural soils. D). Has little to no effect on the carbon cycle.

C). Increases global warming by increasing the production of nitrous oxide (N2O) by identification in agricultural soils.

Bacterial oxidation of Fe2+ occurs BEST under which environmental condition? A). Cold temperature B) .High sunlight C). Low (acidic) pH D). Nutrient-replete

C). Low (acidic) pH