Microorganisms are used for various purposes such as:

● They are used in the preparation of curd, bread and cake.

● They are used in the preparation of alcohol, wine and acetic acid (vinegar).

● They are also used in cleaning up of the environment.

● In agriculture, they are used to increase soil fertility by fixing nitrogen.

● The antibiotics are manufactured by growing specific microorganisms and are used to cure a variety of diseases. Penicillin is an antibiotic made from Penicillium.

● Certain microbes are also used in the biological treatment of sewage and industrial effluents.

● Yeast is used in making idlis, bhaturas, bread, pastries and cakes.