Question

briefly describe how nitrogen of the atmosphere is converted into nitrates by leguminous plant

Answer 1

The nitrogen cycle describes the conversion of nitrogen between different chemical forms. The majority of the earth's atmosphere (about 78%) is composed of atmospheric nitrogen, but it is not in a form that is usable to living things. Complex species interactions allow organisms to convert nitrogen to usable forms and exchange it between themselves. Nitrogen is essential for the formation of amino acids and nucleotides. It is essential for all living things.

Fixation: In order for organisms to use atmospheric nitrogen (N2), it must be "fixed" or converted into ammonia (NH3). This can happen occasionally through a lightning strike, but the bulk of nitrogen fixation is done by free living or symbiotic bacteria. These bacteria have the nitrogenase enzyme that combines gaseous nitrogen with hydrogen to produce ammonia. It is then further converted by the bacteria to make their own organic compounds. Some nitrogen fixing bacteria live in the root nodules of legumes where they produce ammonia in exchange for sugars. Today, about 30% of the total fixed nitrogen is manufactured in chemical plants for fertilizer .