Question

Concept 37.3 (Nitrogen-Fixing Bacteria): How do legumes form a tight mutualism with Rhizobium bacteria? The Rhizobium bacteria live outside the plant (in the soil) and fix nitrogen while living off some sugars that the plant secretes The legume roots form nodules containing Rhizobium bacteria that fix nitrogen for the plant while receiving sugars and other photosynthetic products from the plant The legume roots form nodules containing Rhizobium bacteria that fix phosphorus for the plant while receiving sugars and other photosynthetic products from the plant The bacteria feed on the plant roots while giving back nothing to the plants

Answer 1

Answer: Option 2

Rhizobium is a nitrogen fixing bacteria. It infects the roots of leguminous plants which leads to nodule formation giving the roots a beaded appearance.

The rhizobium fixes atmospheric N2 gas into ammonia which is utilized by the plant for their growth. In exchange,plant provides it with nutrition. This is an example of symbiotic relationship.