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Questions and Answers
What type of organisms are responsible for most nitrogen fixation?
What type of organisms are responsible for most nitrogen fixation?
In addition to prokaryotes, nitrogen can be fixed abiotically by which of the following?
In addition to prokaryotes, nitrogen can be fixed abiotically by which of the following?
Which of the following is NOT a method used by some nitrogen-fixing bacteria to establish symbiosis with plants?
Which of the following is NOT a method used by some nitrogen-fixing bacteria to establish symbiosis with plants?
What is the purpose of the root exudates from legume plants in symbiotic nitrogen fixation?
What is the purpose of the root exudates from legume plants in symbiotic nitrogen fixation?
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Which of the following is true regarding symbiotic nitrogen-fixers?
Which of the following is true regarding symbiotic nitrogen-fixers?
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What characteristic distinguishes aerobic nitrogen-fixing bacteria from anaerobic ones?
What characteristic distinguishes aerobic nitrogen-fixing bacteria from anaerobic ones?
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What is the name of the enzyme complex responsible for the reduction of N2 to NH3 in nitrogen-fixing organisms?
What is the name of the enzyme complex responsible for the reduction of N2 to NH3 in nitrogen-fixing organisms?
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Why is nitrogenase sensitive to oxygen?
Why is nitrogenase sensitive to oxygen?
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Which structure in cyanobacteria provides a low-oxygen environment for the nitrogenase enzyme?
Which structure in cyanobacteria provides a low-oxygen environment for the nitrogenase enzyme?
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How do some photosynthetic nitrogen-fixers protect their nitrogenase from oxygen while carrying out nitrogen fixation?
How do some photosynthetic nitrogen-fixers protect their nitrogenase from oxygen while carrying out nitrogen fixation?
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Where do genes for nitrogenase have been found globally distributed, including in aerobic habitats and anaerobic environments?
Where do genes for nitrogenase have been found globally distributed, including in aerobic habitats and anaerobic environments?
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What characteristic distinguishes symbiotic nitrogen-fixers from other nitrogen-fixers that help them carry out nitrogen fixation efficiently?
What characteristic distinguishes symbiotic nitrogen-fixers from other nitrogen-fixers that help them carry out nitrogen fixation efficiently?
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What is the significance of the broad distribution of nitrogen-fixing genes among organisms?
What is the significance of the broad distribution of nitrogen-fixing genes among organisms?
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Which process converts ammonia to nitrite and then to nitrate in the global nitrogen cycle?
Which process converts ammonia to nitrite and then to nitrate in the global nitrogen cycle?
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What type of microorganisms are responsible for the oxidation of ammonia to nitrite in nitrification?
What type of microorganisms are responsible for the oxidation of ammonia to nitrite in nitrification?
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Why are aerobic ammonia oxidizers considered slow growers?
Why are aerobic ammonia oxidizers considered slow growers?
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In nitrification, what is the intermediate compound formed during the conversion of ammonia to nitrite by ammonia-oxidizers?
In nitrification, what is the intermediate compound formed during the conversion of ammonia to nitrite by ammonia-oxidizers?
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What distinguishes aerobic ammonia oxidizers from other organisms in terms of energy source?
What distinguishes aerobic ammonia oxidizers from other organisms in terms of energy source?
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