AP BIOLOGY

Detailed explanation-1: -Rhizobium attaches to the roots of the leguminous plants resulting in the generation of root nodules. It forms a symbiotic association with the leguminous plants as it draws the nutrition from the plants and in turn helps with the fixation of nitrogen in the soil for the leguminous plants to take up.

Detailed explanation-2: -Rhizobium bacteria are found in the root nodules of leguminous plants such as peas and beans.

Detailed explanation-3: -Root-nodule bacteria (rhizobia) are of great importance for nitrogen acquisition through symbiotic nitrogen fixation in a wide variety of leguminous plants. These bacteria differ from most other soil microorganisms by taking dual forms, i.e. a free-living form in soils and a symbiotic form inside of host legumes.