Question

What is root nodules? Why it is present in roots of plants.

Answer 1

Nitrogen is the most commonly limiting nutrient in plants. Legumes use nitrogen fixing bacteria, specifically symbiotic rhizobia bacteria, within their root nodules to counter the limitation. Rhizobia bacteria fix nitrogen which is then converted to ammonia.

Bacteria living in the root nodules fix atmospheric nitrogen to the plant. Plantscannot utilize atmospheric nitrogen directly. Hence, leguminous plants establish a symbiotic relationship with bacteria like Rhizobium. ... Some plants contain root nodules which have rhizobium bacteria