bacteria involved in the nitrogen cycle

which type of bacteria is involved with nitrogen fixation?

nitrogen fixing bacteria- rhizobium

where is rhizobium found and what is it's role?

it is found free in the soil in the presence of limited amounts of nitrogen and it fixes atmospheric nitrogen

how does bacteria fix nitrogen?

it uses nitrogenase and converts nitrogen into ammonium using hydrogen, ATP and anaerobic conditions, it is fixed into forms other organisms can use

which type of bacteria is involved with ammonification?

ammonifying bacteria (decomposers)

what happens in the process of ammonification?

decomposers breakdown proteins in dead organisms and animal waste, releasing ammonium ions

what happens in the process of nitrification?

1. ammonia or ammonium ions are oxidised to form nitrites
2. the nitrites are oxidised to form nitrates, which is the form most usable by plants

Which type of nitrifying bacteria is involved in converting ammonium to nitrites?

Nitrosomonas

which type of bacteria is involved with nitrification?

nitrifying bacteria = Nitrosomonas and Nitrobacter

Which type of nitrifying bacteria is involved in converting nitrites to nitrates?

Nitrobacter

which type of bacteria is involved with denitrification?

denitrifying bacteria

what is the energy source of nitrifying bacteria?

they use inorganic salts as an energy source and generally cannot utilise organic materials

what happens in denitrification?

nitrates are reduced to nitrogen gas, returning nitrogen to the air and completing the cycle

what is the order of the 4 processes in the nitrogen cycle?

nitrogen fixation-> ammonification-> nitrification-> denitrification

what are the conditions required for ammonification?

aerobic/anaerobic

what are the conditions required for nitrogen fixation?

aerobic/anaerobic

what are the conditions required for nitrification?

aerobic

what are the conditions required for denitrification?

anaerobic