Microbes like Saccharomyces cerevisiae are utilized in the commercial production of ethanol. Enzyme production is another application of microbes, with lipases being used in detergent formulations to effectively remove oily stains from laundry. It is common to observe that commercially bottled fruit juices appear clearer compared to homemade ones, as the former undergo clarification processes employing pectinases and proteases. Streptokinase, produced by the bacterium Streptococcus and genetically modified, serves as a "clot buster" in the removal of blood clots from the vessels of individuals who have experienced a heart attack. Cyclosporin A, another bioactive molecule, is derived from the fungus Trichoderma polysporum and is employed as an immunosuppressive agent in organ transplant patients. Statins, on the other hand, are produced by the yeast Monascus purpureus and have been commercialized as agents to lower blood cholesterol levels. They function by competitively inhibiting the enzyme responsible for cholesterol synthesis. Biofertilizers are organisms that enhance the nutrient quality of the soil and can be derived from bacteria, fungi, and cyanobacteria. Rhizobium bacteria form nodules on the roots of leguminous plants and convert atmospheric nitrogen into organic forms, which serve as nutrients for the plants. Additionally, certain free-living bacteria like Azospirillum and Azotobacter can fix atmospheric nitrogen in the soil, thereby enriching its nitrogen content .Fungi also engage in symbiotic associations with plants, known as mycorrhiza. Many members of the Glomus genus form mycorrhiza, wherein the fungal symbiont absorbs phosphorus from the soil and transfers it to the plant. These associations offer various benefits to the plants, including enhanced resistance to root-borne pathogens, increased tolerance to salinity and drought, and an overall improvement in plant growth and development.

What are biofertilizers?

Organisms that enrich the nutrient quality of the soil.

The correct answer is b.

Biofertilisers are organisms that enrich the nutrient quality of the soil.

They are not chemical substances, but rather living organisms such as bacteria, fungi, and cyanobacteria.

These organisms have the ability to fix atmospheric nitrogen, solubilize nutrients, and enhance nutrient availability in the soil.

They form symbiotic associations with plants or directly release beneficial substances into the soil, thereby promoting plant growth and improving soil fertility.

Biofertilisers are considered a more sustainable and environmentally friendly alternative to chemical fertilisers, as they work in harmony with natural processes and do not cause harmful effects on the soil or ecosystem.