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Microbes in Human Welfare

Short Answer Type

61. Define BOD and COD.

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62. Do you think microbes can be used as source of energy ? If yes, how ?

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63. Microbes can be used to lessen the burden of use of chemical pesticides. Explain how this can be accomplished.

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64. Write a short note on natural insecticides.

Natural insecticides are chemicals, minerals, or biological which kill, repel, or prevent the insect pests from damaging the crops.

For exampls- Extracts from neem (Azadirachta indica) contain a compound, azadirachtin that keeps away the insects. Foliage coated with extract of neem repel Japanese beetles and leaf eating pests.

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65. What is biopesticide ? Give a few examples.

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66. What for Nucleopolyhydro viruses are being used now a days?

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67. What are biofertilizers ? Name two organims which fix nitrogen asymbiotically and two organisms with fix symbiotically.

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68. Why are biofertilizers or biopesticides preferred to chemical fertilizers or pesticides ?

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69. What is biogas ?

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70.

Why is the biogas plant usually built in the rural area?

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