The 10 lines on the usefulness of microorganisms are:-

1) It  is used in the commertial manufacturing of alcohol and acetone.

2) Some bacteria are used to obtain medicines like antibiotics, serums and vaccines.

3) certain microorganisms have a key role in agriculture.

4)They are responsible for nitrification, i.e, The process of conversion of ammonia to nitrates.

5) Some microorganisms stay in the intestine of living beings and helps them in digestion.

6)microorganisms like yeast are used in the formation of cake, bread, cheese, etc.

7)They act as the cleansing agent of our ecosystem.

8)Yeasts are nutritional supplement as they contain vitamin b and e.

9)The lactobacillus bacteria, is used for the manufacturing of curd from milk.

10)They are used for the curing and ripening of tea and tobacco leaves to develop characteristic aroma and flavour.

hoped helped u :))

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