Solution: Only a few living creatures can use nitrogen in the form of N2, which is plentiful in the air. Only a few bacterial species have the ability to fix nitrogen. Nitrogenase, a nitrogen reduction enzyme, is only found in prokaryotes. These bacteria are known as N2-fixers. The process of nitrogen fixation is the conversion of atmospheric nitrogen to ammonia (NH3) in the presence of the enzyme Nitrogenase. Since, nitrogenase is present in prokaryotes, this process occurs.