The rising of dough is due to:
1. Multiplication of yeast
2. Production of CO2
3. Emulsification
4. Hydrolysis of wheat flour starch into sugars
Methanogenic bacteria are not found in:
1. rumen of cattle
2. gobar gas plant
3. bottom of water-logged paddy fields
4. activated sludge
The technology of biogas production from cow dung was developed in India largely due to the efforts of:
1. | Gas Authority of India |
2. | Oil and Natural Gas Commission |
3. | Indian Agricultural Research Institute and Khadi & Village Industries Commission |
4. | Indian Oil Corporation |
The free-living fungus Trichoderma can be used for:
1. killing insects
2. biological control of plant diseases
3. controlling butterfly caterpillars
4. producing antibiotics
Mycorrhiza does not help the host plant in:
1. | Enhancing its phosphorus uptake capacity |
2. | Increasing its tolerance to drought |
3. | Enhancing its resistance to root pathogens |
4. | Increasing its resistance to insects |
Which one of the following is not a nitrogen-fixing organism?
1. | Anabaena | 2. | Nostoc |
3. | Azotobacter | 4. | Pseudomonas |
The residue left after methane production from cattle dung is:
1. | burnt | 2. | buried in landfills |
3. | used as manure | 4. | used in civil construction |
Methanogens do not produce:
1. | oxygen | 2. | methane |
3. | hydrogen sulfide | 4. | carbon dioxide |
What would happen if oxygen availability to activated sludge flocs is reduced?
1. | It will slow down the rate of degradation of organic matter. |
2. | The center of flocs will become anoxic, which would cause the death of bacteria and eventually breakage of flocs. |
3. | Flocs would increase in size as anaerobic bacteria would grow around flocs. |
4. | Protozoa would grow in large numbers. |
During which stage of the sewage treatment are the microbes used?
1. | Primary | 2. | Secondary |
3. | Tertiary | 4. | Quaternary |