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In nitrogen cycle the step ‘Nitrogen assimilation' involves -
(A) Conversion of ammonium compounds in ammonia by bacteria
(B) Conversion of atmospheric nitrogen into nitrites and nitrates by blue green algae
(C) Conversion of ammonia into nitrites by bacteria present in the soil
(D) Absorption of nitrogen by the plants in the form of nitrates to prepare
amino acids
Answers
Answer:
The entire process of Nitrogen fixation is completed by symbiotic bacteria which are known as Diazotrophs. Azotobacter and Rhizobium also have a major role in this process. These bacteria consist of a nitrogenase enzyme which has the capability to combine gaseous nitrogen with hydrogen to form ammonia.
Answer:
1 Nitrificaton: Nitrification is the conversion of ammonia (NH3) to nitrate (NO3–). It is usually performed by soil living bacteria, such as nitrobacter. This is important because plants can assimilate nitrate into their tissues, and they rely on bacteria to convert it from ammonia to a usable form.
2 Nitrogen-fixing bacteria in the soil and within the root nodules of some plants convert nitrogen gas in the atmosphere to ammonia. Nitrifying bacteria convert ammonia to nitrites or nitrates. Ammonia, nitrites, and nitrates are all fixed nitrogen and can be absorbed by plants.
3 The nitrification process requires the mediation of two distinct groups: bacteria that convert ammonia to nitrites (Nitrosomonas, Nitrosospira, Nitrosococcus, and Nitrosolobus) and bacteria that convert nitrites (toxic to plants) to nitrates (Nitrobacter, Nitrospina, and Nitrococcus).
4 Nitrogen assimilation in plants. Plants absorb nitrogen from the soil in the form of nitrate (NO3−) and ammonium (NH4+). ... Nitrogen is transported from the root to the shoot via the xylem in the form of nitrate, dissolved ammonia and amino acids.