HARD
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Select the correct options from the following statements w.r.t. activated sludge:

A. After secondary treatment, microbial flocs are allowed to settle down, which is called as activated sludge.

B. The major part of the sludge is pumped into large tanks called anaerobic sludge digester.

C. It is generally released into natural water bodies like rivers and streams.

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Important Questions on Microbes in Human Welfare

EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
In STP the biological treatment is completed with the help of
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Sewage water can be purified by:
MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Two bottles were half-filled with water from Ganga (P) and Kaveri (Q) and kept under identical airtight conditions for 5 days. The oxygen was determined to be 2% in the bottle (P) and 10% in the bottle (Q). What could be the cause of this difference?
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Which bacteria is commonly found in the anaerobic sludge during sewage treatment?
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Write a brief note on biochemical oxygen demand.
MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Choose the correct option, which shows correct sequence of substances obtained during sequential process of sewage treatment.
EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
The microorganisms involved in floc formation during sewage treatment are
EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Study the following statements and select the incorrect ones?
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Describe the role of Microbes in sewage treatment plant.
EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Which of the following is put into Anaerobic sludge digester for further sewage treatment?
MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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HARD
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Differentiate between the primary and secondary treatment of sewage. 
HARD
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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MEDIUM
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
When students visited sewage treatment plants in their city, they observed large airtight tanks with huge pipelines to collect the released gases so as to generate electricity. As a student of Biology, explain the formation and composition of these gases in the tanks.
EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Activated sludge have the ability to settle quickly so that it can:
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Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
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EASY
Biology>Plants, Microbes and Human Welfare>Microbes in Human Welfare>Microbes in Sewage Treatment
Which of the following in sewage treatment removes suspended solids?