Nitrogen Metabolism — Flashcards

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The main form of nitrogen in the atmosphere is molecular nitrogen (N₂), which makes up about 78% of the air. It exists as a highly stable triple-bonded molecule (N≡N) and cannot be directly used by mo…

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Plants cannot use atmospheric nitrogen (N₂) because it is chemically very stable due to its triple bond (N≡N). They require nitrogen in a 'fixed' form like ammonia (NH₃) or nitrates (NO₃⁻) that can be…

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Nitrogen fixation is the process by which atmospheric nitrogen (N₂) is converted into ammonia (NH₃) or related compounds that can be used by plants. This process can occur through biological or abiolo…

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The two types of nitrogen fixation are: (1) Abiological (non-living) fixation, which occurs through lightning or industrial Haber's process, and (2) Biological fixation, carried out by certain microor…

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An example of abiological nitrogen fixation is the formation of nitrogen oxides (NO, NO₂) during thunderstorms. The high temperature and pressure from lightning cause nitrogen and oxygen to react, for…

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The Haber's process is an industrial method of nitrogen fixation where nitrogen gas (N₂) and hydrogen gas (H₂) are combined under high pressure and temperature in the presence of a catalyst to produce…

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The enzyme responsible for biological nitrogen fixation is nitrogenase. It catalyzes the conversion of atmospheric nitrogen (N₂) into ammonia (NH₃) in nitrogen-fixing bacteria.

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Nitrogenase is sensitive to oxygen because oxygen irreversibly inactivates the enzyme. To protect nitrogenase, nitrogen-fixing bacteria either create anaerobic conditions or produce protective protein…