nitrogen cycle in bacteria and fungi?

Question

i am doing an essay and need info
any good websites would be very usefull :D thankyou

Answer 1

The Nitrogen Cycle is responsible for releasing the Nitrogen which has been "fixed" in organisms and allowing it to return to the atmosphere. Around 79% of the atmosphere is Nitrogen and this element is essential for Protein formation. Unfortunately most plants can only absorb Nitrogen from the soil in the form of Nitrates. Other organisms that are incapable of fixing their own Nitrogen must get it from eating plants or eating animals that eat plants.
The Nitrogen in the air can be "fixed" by certain plants that have root nodules in which a bacteria called Rhizobium lives. This bacteria is able to use atmospheric Nitrogen and fix it into a form that plants can use. This process is known as Nitrogen Fixation. Lightning can also fix atmospheric Nitrogen into Nitrates that can be uptaken by plants. Animals eat plants and incorporate the Nitrogen in them into their own structure. This Nitrogen is released when the animal dies or when faeces and urine are passed out. The compounds containing Nitrogen are broken down by bacteria and fungi in a process called decomposition. The bacteria and fungi are called decomposers. This breakdown releases Nitrogen as Ammonium compounds in the soil and further breakdown by other bacteria results in the formation of Nitrites and then Nitrates. THis is known as Nitrification. Some of the nitrates in the soil may be broken down by bacteria to release Nitrogen back into the atmosphere. This is known as dentrification.

Answer 2

Just a little help. One of the major sources of nitrogen for plants is Lightning . Each lightening strike produces as much as 300 lb. of NO2 .

Answer 3

try this
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/N/NitrogenCycle.html