Pull out a gram or bean plant from the field. Observe its roots. You will find round structures called root nodules on the roots. Draw a diagram of the root and show the root nodules.

AcademicBiologyNCERTClass 8

Root nodules of certain plants, such as peas and beans, have extra lobes in which nitrogen-fixing bacteria are found. Leguminous plants are plants with root nodules. Bacteria in these root nodules convert atmospheric nitrogen into nitrates, which the plants can utilize. The plants use this nitrogen to synthesize proteins and other materials.

                                                                                                  Root Nodules 

Extra information:

Nitrogen fixation: It is the initial step of the nitrogen cycle in which atmospheric nitrogen (N2) is converted into ammonia.

During nitrogen fixation, the inert nitrogen gas gets deposited into soils from the atmosphere through precipitation. Then the two nitrogen atoms get separated and combine with hydrogen to form ammonia (NH4+).

Some nitrogen-fixing bacteria include Azotobacter, Rhizobium, and some Archaea.

Nitrogen Cycle is a biogeochemical process in which nitrogen is converted into multiple forms. In this cycle, nitrogen consecutively passes from the atmosphere to the soil to organism and back into the atmosphere. It involves important processes such as nitrogen fixation, nitrification, assimilation, ammonification, and denitrification.


Updated on 10-Oct-2022 12:46:41