The primary treatment of sewage involves:
1. Digestion
2. Decomposition
3. Sedimentation and filtration
4. None of these
The amount of oxygen required by the microbes in the decomposition of organic matter is called:
1. Chemical oxygen demand
2. Biochemical oxygen demand
3. Total oxygen demand
4. Dissolve oxygen
The mixture of gases released during anaerobic digestion of sludge is called:
(1) Methane
(2) Carbon dioxide
(3) Biogas
(4) Flammable gases
Biogas contains:
(1) CO2
(2) H2S
(3) CH4
(4) All of these
The symbiotic association between fungi and roots of higher plants is called:
1. Lichen
2. Mycorrhiza
3. Biofertilizer
4. BOD
The organisms which are used to enrich the nutrient quality of the soil are called:
1. Mycorrhiza
2. Biofertilizers
3. Yeast
4. Methanogens
Which of the following serve as biofertilizer in paddy fields?
(1) Bacteria
(2) Yeast
(3) Cyanobacteria (blue-green algae)
(4) Fungi
The solids which settle after primary treatment of sewage are called:
(1) Primary sludge
(2) Activated sludge
(3) Flocs
(4) Total solids
Given below are three statements (A-B) each with one or more blanks. Select the option which correctly fills the blanks in the statements Statements:
A. | Bioactive molecule, ________ is used as immunosuppressive agent in organ transplant patients, It is produced by the fungus ________. |
B. | Primary treatment of sewage involves physical removal of small and large particles through ________. |
1. A - Antibiotic, Trichoderma polysporum; B - filtration and sedimentation
2. A - Cyclosporin A, Trichoderma polysporum; B - filtration and sedimentation
3. A - Cyclosporin A, Trichoderma polysporum; B - Centrifugation and sedimentation
4. A - Antibiotic, Trichoderma polysporum; B - Centrifugation and sedimentation
Given below are three statements (A-B) each with one or more blanks. Select the option which correctly fill the blanks in the statements Statements:
A. Microbes consume the major part of the organic matter in the effluent and reduce _________ of sewage.
B. Certain bacteria which grow anaerobically on cellulosic material, produce large amount of methane along with CO2 and H2. The bacteria are commonly called as _________ and one such common bacterium is _________. Options:
(1) A - CO2 demand; B - methanogens, Methanobacterium
(2) A - Carbon; B - methanogens, Methanobacterium
(3) A - biochemical oxygen demand; B - methanogens, Methanobacterium
(4) A - biochemical oxygen demand; B - Methylokorus infemorum