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Microbes in Human Welfare

Short Answer Type

31. 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 ?

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32. Give examples to prove that microbes release gases during metabolism.

1. Large holes in ‘Swiss Cheese’ are due to production of large amount of C0₂released 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.

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33. How is curd prepared ? How prepration of curd improves its nutritional value ?

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34. Make a list of any 3 Milk products obtained from the activities of bacteria.

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35.

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

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

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

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38. Make a table showing industrial products obtained from activities of bacteria.

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39. Tabulate the list of common antibiotics, organisms producing them

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40. What are “broad spectrum antibiotics” ?

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