Question

please tell me Easy steps of nitrogen cycle (5 marks)

Answer 1

The nitrogen cycle describes how nitrogen moves between plants, animals, bacteria, the atmosphere (the air), and soil in the ground. Nitrogen is an important element to all life on Earth. 

Different Nitrogen States 

For Nitrogen to be used by different life forms on Earth, it must change into different states. Nitrogen in the atmosphere, or air, is N2. Other important states of nitrogen include Nitrates (N03), Nitrites (NO2), and Ammonium (NH4). 

Nitrogen Cycle 

This picture shows the flow of the nitrogen cycle. The most important part of the cycle is bacteria. Bacteria help the nitrogen change between states so it can be used. When nitrogen is absorbed by the soil, different bacteria help it to change states so it can be absorbed by plants. Animals then get their nitrogen from the plants. 



Processes in the Nitrogen Cycle

Fixation - Fixation is the first step in the process of making nitrogen usable by plants. Here bacteria change nitrogen into ammonium.

Nitrification - This is the process by which ammonium gets changed into nitrates by bacteria. Nitrates are what the plants can then absorb.

Assimilation - This is how plants get nitrogen. They absorb nitrates from the soil into their roots. Then the nitrogen gets used in amino acids, nucleic acids, and chlorophyll.

Ammonification - This is part of the decaying process. When a plant or animal dies, decomposers like fungi and bacteria turn the nitrogen back into ammonium so it can reenter the nitrogen cycle.

Denitrification - Extra nitrogen in the soil gets put back out into the air. There are special bacteria that perform this task as well.

hope this helps uu...!!!

Answer 2

1) Nitrogen fixation-This step is characterised by the conversion of atmospheric N2 into ammonia (NH3). Bacteria like Azotobacter and Rhizobium have a major role in this process.

2) Assimilation- Once nitrogen has been fixed in the soil, plants can absorb nitrogen through their roots.

3) Ammonification-This is another process by which ammonia can be generated. Organic remains of plants and animals are broken down in the soil by some bacteria to release ammonia into the soil. These dead and waste matter is used by these microorganisms as food and they release ammonia into the soil.

4) Nitrification-This occurs in two-steps. The first step is in which NH3 is converted to NO3- (nitrates). The bacteria Nitrosomonas and Nitrococcus present in the soil convert NH3 to NO2-, and another bacterium, Nitrobacter converts NO2- to NO3-. These bacteria gain energy through these conversions.

5) Dendrification-Is the reverse of nitrification that occurs in the deep layers of soil where the bacteria convert NO3- is converted into N2 and other gaseous compounds like NO2