Skip to main content

# 3.4: Prokaryotic Cells

Photosynthesis is one of the major ecological roles cyanobacteria currently have in modern day ecosystems. Another is nitrogen fixation. Nitrogen is an essential nutrient for plants, yet it is difficult to obtain in many ecosystems. Though it is abundant in our atmosphere, this form a nitrogen ($$\ce{N2}$$) is triple-bonded to itself, a bond which most organisms cannot break. However, certain bacteria have an enzyme called nitrogenase that can break the triple bond and convert nitrogen into usable forms for plants, such as ammonia ($$\ce{NH3}$$). These bacteria can be found free-living in the environment or in mutualistic relationships with certain plants.

## Contributors and Attributions

• Was this article helpful?