Question

i. In which form, Nitrogen cannot be used?
ii. Define Ammonification.
iii. Name any two organic nitrogen molecules.
iv. What is denitrification?
V. What is meant by nitrogen cycle?​

Answer 1

i)Nitrogen in its gaseous form (N2) can't be used by most living things. It has to be converted or 'fixed' to a more usable form through a process called fixation.

ii)The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. 

iii)Nitrogen forms many thousands of organic compounds. Most of the known varieties may be regarded as derived from ammonia, hydrogen cyanide, cyanogen, and nitrous or nitric acid. The amines, amino acids, and amides, for example, are derived from or closely related to ammonia.

iv)Denitrification is defined as the “microbial reduction of nitrate or nitrite coupled to electron transport phosphorylation resulting in gaseous N either as molecular N2 or as an oxide of N.” The key to denitrification as defined is the availability of the N oxides, nitrite (NO2−) or nitrate (NO3−), which are formed

v)The nitrogen cycle is the circulation of nitrogen in various forms through nature. Learn more about... Nitrates and ammonia resulting from nitrogen fixation are assimilated into the specific tissue compounds of algae and higher plants.

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