nitrogen cycle

what is the diffference between inorganic and organic nitrate

inorganic = no carbon found in soil makes amino acids

organic = with carbon

nitrogen vs nitrate vs nitrogen

Substance	Formula	Type	Where Found	Used By Plants?	Key Role
Nitrogen gas	N₂	Inorganic gas	Air	❌ No	Must be fixed first
Nitrite	NO₂⁻	Inorganic ion	Soil	❌ No	Intermediate step
Nitrate	NO₃⁻	Inorganic ion	Soil	✅ Yes	Main nitrogen source for plants

why is nitrogen needed

to make proteins CHONS and amino acids CHONP

what are the 3ways we can fix nitrogen 

Nitrogen fixing bacteria = these reduce nitrogen gas to ammonia which dissolves to form ammonium ions.

harbour process= done by humans to make fertilisers

lightning= fixes nitrogen by oxidising it 

what do nitrifying bacteria do

they take the ammonia and they cause a reaction which produces nitrile (step 1) then that is converted into nitrate (step 2). each step done by a different type of bacteria 

what is assimilation

they is when the nitrate ions are taken up by the roots. They use active transport to move the ions into the root hair cells. Some have symbiotic fungi which help

decomposition or ammonification

when plants and animals dye the DNA and amino acids which contain nitrogen is Broken down and ammonia is formed.

step 1 digestion this breaks down protein in amino acids

step 2 deamination this breaks them down into carbohydrates which can be used for respiration. This process the Nitrogen is removed in the form of ammonia.

dentification 

• Happens in soil when oxygen is low (anaerobic conditions).

• Denitrifying bacteria (e.g. Pseudomonas) carry it out.

• They convert nitrates (NO₃⁻) → nitrogen gas (N₂).

• Nitrogen gas is released back into the atmosphere.

• This process reduces soil fertility (less nitrate for plants).