Question

Give an example of a nitrogen fixer that is free-living.

Answer 1

Nitrogen fixation:

1. Certain bacteria and prokaryotes can transform nitrogen from the air into ammonia.
2. This is referred to as biological nitrogen-fixing.
3. Nitrogenase is an enzyme that transforms nitrogen into ammonia.
4. Free-living or symbiotic nitrogen-fixing microorganisms exist in nature.

Example:

1. Some free-living nitrogen-fixers are Nostoc and Anabaena.
2. Nostoc and Anabaena are genus of blue-green algae or cyanobacteria.
3. They are prokaryotic and photosynthesis is carried out by them.
4. They have the ability to fix nitrogen with the help of specialised cells called heterocysts.