Question

Some blue-green algae can be used as biofertilizers because they are:

• A. Photosynthetic
• B. Surrounded by mucilage
• C. Growing everywhere
• D. Can fix atmospheric nitrogen

Answer 1

The correct option is D

Can fix atmospheric nitrogen

These are normally found in symbiotic relationships with higher plants and one of the benefits of their association is that they help in increasing the fertility of the soil by fixing atmospheric nitrogen into nitrates.