Question 7
Write 10 lines on the usefulness of microorganisms in our lives.
Micro-organisms are too small to be seen through the naked eye. However, they are vital to humans, plants and the environment.
i. Lactobacillus is used to form curd from milk.
ii. Rhizobium present in the roots of leguminous plants fix nitrogen from the air and supply nitrogen compounds to these plants.
iii. Micro-organisms are also used in winemaking, baking, pickling, and other food making processes.
iv. Alcoholic fermentation by yeast is widely used in the preparation of wine and bread.
v. Microbes are used to reduce pollution. For example, certain bacteria and fungi decompose dead bodies and excreta to form inorganic compounds, which can be absorbed by plants.
vi. Microbes also play an important role in the preparation of medicines. Antibiotics are chemicals produced by micro-organisms to kill bacteria. Penicillin is an antibiotic obtained from the fungi called Penicillium.
vii. Bacteria present in our intestine helps in proper digestion and synthesise certain vitamins which are absorbed by the intestine.
viii. Many vaccines are prepared from micro-organisms. These vaccines help in attaining immunity against a disease.
ix. Certain microbes are also used in the biological treatment of sewage and industrial effluents.
x. Yeast is used in making idli, bhatura, bread, pastries and cakes.