Micro-organisms are too small to be seen through naked eyes. However, they are vital to plants and the environment.
They are used in winemaking, baking, pickling, and other food making processes.
Alcoholic fermentation by yeast is widely used in the preparation of wine and bread. A bacterium Lactobacillus, promotes the formation of curd.
Microbes are used to reduce pollution. For example, decomposers such as bacteria and fungi break down dead bodies and excreta to form inorganic compounds, which can be absorbed by plants.
They are used to increase the soil fertility by fixing the atmospheric nitrogen with the help of bacterium Rhizobium and some other blue-green algae.
Microbes also play an important role in the preparation of medicines. Antibiotics are chemicals produced by micro-organisms to kill bacteria. Streptomycin, for example, is an antibiotic.
Certain microbes are also used in the biological treatment of sewage and industrial effluents.