Draw nitrogen cycle for class 9
Answers
Answer:
Nitrogen is a part of many molecules essential to life like proteins,Nucleic acid(DNA and RNA) and some vitamins. It is found in alkaloids,urea.
(1) Aerial nitrogen cannot be used as such by majority of organism.
(2) There are certain bacteria which convert this inert nitrogen into nitrates and nitrites which can be taken up and used to make required molecules.
(3) During lightning the high temperature and pressure created in the air converts nitrogen into oxides of nitrogen.These oxides dissolve in water to give nitric and nitrous acid and fall on land along with rain.
(4) Nitrates are absorbed by plants into their system and utilised for making organic matter(proteins)
(5) When animals consume plant matter,they break down the plant’s nitrogenous compounds and use them to form new animal proteins.
(6) After an animal excretes urea or uric acid or after an animal or plant dies,certain bacteria carry out ammonification ie they produce ammonium ions from nitrogen containing molecules.
(7) Plants can then assimilate this ammonium ion or still other bacteria can change it to nitrate by nitrification.
The process of ammonia formation is called ammonification.Some micro-organism(nitrobacteria, nitrosomonas)convert ammonia into nitrates.The process is called nitrification.
There are certain bacteria which reduce nitrates back to nitrogen or to ammonia or to some other oxides.This process is called denitrification.
Answer:
Explanation:
→ Nitrogen Cycle is a biogeochemical process through which nitrogen is converted into many forms, consecutively passing from the atmosphere to the soil to organism and back into the atmosphere.
→ It involves several processes such as nitrogen fixation, nitrification, denitrification, decay and putrefaction.
→ The nitrogen gas exists in both organic and inorganic forms. Organic nitrogen exists in living organisms, and they get passed through the food chain by the consumption of other living organisms.
→ Inorganic forms of nitrogen are found in abundance in the atmosphere. This nitrogen is made available to plants by symbiotic bacteria which can convert the inert nitrogen into a usable form – such as nitrites and nitrates.
→ Nitrogen undergoes various types of transformation to maintain a balance in the ecosystem. Furthermore, this process extends to various biomes, with the marine nitrogen cycle being one of the most complicated biogeochemical cycles.
