Question

Nitrogen from the atmosphere must be converted into ammonia (NH3) for use by plants. The organisms that add this molecule to the soil are nitrogen-fixing bacteria, such as Rhizobium, Azotobacter, and others. These bacteria have the ability to fix atmospheric nitrogen into ammonia, making it available to plants.

Answer 1

Nitrogen-fixing bacteria convert atmospheric nitrogen into ammonia, making it available to plants. This ammonia can be assimilated by plants and is the primary source of nitrogen used by them.

Step-by-step explanation:

Nitrogen-fixing bacteria convert atmospheric nitrogen into ammonia through a process known as nitrogen fixation. These bacteria, such as Rhizobium and Azotobacter, have the ability to fix atmospheric nitrogen into ammonia, making it available to plants. This ammonia can then be oxidized to nitrite and nitrate, which can be assimilated by plants. Nitrogen fixation is the primary source of nitrogen used by plants in most ecosystems.