Question

Which of the following sequences depicts the steps in nitrogen cycle accurately?

• A. Nitrogen fixation$\to$Assimilation$\to$Nitrification$\to$Ammonification$\to$Denitrification
• B. Nitrogen fixation$\to$Nitrification$\to$Ammonification$\to$Assimilation$\to$Denitrification
• C. Nitrogen fixation$\to$Nitrification$\to$Assimilation$\to$Denitrification$\to$Ammonification
• D. Nitrogen fixation$\to$Nitrification$\to$Assimilation$\to$Ammonification$\to$Denitrification

Answer 1

The correct option is D Nitrogen fixation$\to$Nitrification$\to$Assimilation$\to$Ammonification$\to$Denitrification

The nitrogen is first fixed by the microbes present in the soil from it's raw form into it's organic form. Upon their death, the nitrogen is taken up by the plants in the form of nitrates. The plants then use the nitrates to synthesize amino acids and proteins. Ammonia is then formed from the animal wastes and also when the plants and the animals die. And finally the denitrifying bacteria release the nitrogen in it's free form back into the atmosphere via decomposition.