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Microbes in Human Welfare

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12
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Find out the name of the microbes from which Cyclosporin A (an immunosuppressive drug) and Statins (blood cholesterol lowering agents) are obtained.

1. Cyclosporin A is produced by Trichoderma polysporum.

2. Statin is produced by Aspergillus.


Name any two species of fungus, which are used in the production of antibiotics.

Two fungus used in the production of antibiotics are -:

(i) Penicillin chrysogenum

(ii) Cephalosporium


In which way microbes have played a major role in controlling diseases caused by harmful bacteria ?


Antibiotics produced by microbes play a major role in controlling diseases caused by harmful bacteria. The antibiotics retard or stop the growth of various microbes and thus the disease can be cured.

Example : Penicillin produced by Penicillium chrysogenum is active against various species of Staphylococci and Streptococci.


Give examples to prove that microbes release gases during metabolism.

1. Large holes in ‘Swiss Cheese’ are due to production of large amount of C02 released by a bacterium named Propionibacterium sharmanii.

2. The puffed up appearance of dough is due to the production of C02 gas by yeast, Saccharomyces cerevisiae.

3. Methane, H2S and C02 are produced during microbial digestion of organic compounds in case of secondary treatment of sewage.



Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes under a microscope, which sample would you carry and why ?

The sample that can be easily carried is the curd. Curd contains the lactic acid bacteria (Lactobacillus) in large amount, so they can be easily observed. Lactic acid bacteria are also non-pathogenic, so there will be no risk of infection in case of mishandling.

Name some traditional Indian foods made of wheat, rice and Bengal gram (or their products) which involve use of microbes.

Traditional Indian foods made of-:
Wheat - are bread and cake, muffins etc.
Rice -are  idli , dosa, uttapam
Bengal gram - are Dhokla , Khandvi.