The nitrogen cycle Flashcards
What happens during nitrogen fixation?
nitrogen is converted into ammonium or ammonia
Which process are Rhizobium and Azotobacter required for?
Nitrogen fixation
Which nitrogen fixing bacteria is found in roots and which is found in soil?
Rhizobium is found in roots and Azotobacter is found in soil.
What happens in Nitrification?
ammonia/ammonium is oxidised into nitrite ions which are then oxidised into nitrate ions.
What is the job of Nitrosomonas?
To oxidise ammonia/ammonium into nitrite ions
What is Nitrobacter used for?
oxidising nitrite ions into nitrate ions
Which two ions are highly soluble?
nitrite and nitrate
What is ammonification?
The process by which dead organisms are broken down and converted into ammonia/ammonium
What is saprotrophic bacteria used for?
Ammonification
What three parts of dead organism are broken down in ammonification?
proteins, nucleic acid and vitamins
What is denitrification?
nitrate ions in soil are converted to nitrogen gas
Which process requires anaerobic conditions?
denitrification
What enzyme does the nitrogen fixing bacteria contain and what is the process?
nitrogenase which converts nitrogen and hydrogen into ammonia
