Each question in this quiz is timed.
Which stage of the nitrogen cycle converts nitrogen gas into nitrogen-containing compounds?
Ammonification
Nitrification
Nitrogen-fixation
Denitrification
Which stage of the nitrogen cycle produces ammonia from organic ammonium-containing compounds?
Which stage of the nitrogen cycle is involved in the conversion of ammonium ions to nitrate ions?
Which stage of the nitrogen cycle involve denitrifying bacteria which convert soil nitrates into gaseous nitrogen?
What are the two main types of microorganisms that carry out nitrogen fixation?
Saprobiotic bacteria
Free-living nitrogen-fixing bacteria
Denitrifying bacteria
Mutualistic nitrogen-fixing bacteria
What do free-living nitrogen-fixing bacteria do?
Reduce gaseous nitrogen to ammonia, which they then use to manufacture amino acids
Turn ammonia into gaseous nitrogen, which they then use to manufacture amino acids
Mutualistic nitrogen-fixing bacteria live in nodules of roots and plants e.g. peas and beans
Mutualistic nitrogen-fixing bacteria obtain fats from the plant and the plant acquires amino acids from the bacteria
Soils must be well aerated to prevent the build-up of denitrifying bacteria
