During which stage of the sewage treatment are the microbes used?
1. | Primary | 2. | Secondary |
3. | Tertiary | 4. | Quaternary |
Biogas is a mixture of:
1. | Methane, Carbon dioxide, and Hydrogen sulfide |
2. | Methane, Carbon dioxide, and Ammonia |
3. | Methane, Ammonia, and Hydrogen sulfide |
4. | Ammonia, Carbon dioxide, and Hydrogen sulfide |
‘Toddy’, a traditional drink of some parts in southern India, is made by fermenting sap from:
1. | Soyabean | 2. | Bamboo shoots |
3. | Palms | 4. | Sugarcane |
The ‘Roquefort cheese’ is ripened by:
1. | A fungus | 2. | A bacterium |
3. | An algae | 4. | Lichens |
With reference to human beings, antibiotics are actually:
1. | Anti life | 2. | Pro-life |
3. | Irrelevant to life | 4. | Defining life |
Match each item in Column I [Diazotroph] with the feature in Column II and select the correct answer from the codes given below:
|
Column I |
|
Column II |
A. |
Cyanobacteria |
a. |
Actinorhizal symbiont |
B. |
Frankia |
b. |
Do not form nodules |
C. |
Rhizobium |
c. |
Free-living nitrogen fixer |
D. |
Azotobacter |
d. |
Legume symbiont |
Codes
A | B | C | D | |
1. | a | b | c | d |
2. | b | a | c | d |
3. | a | b | d | c |
4. | b | a | d | c |
Aspergillus niger is used in the commercial production of:
1. | Citric acid | 2. | Acetic acid |
3. | Lactic acid | 4. | Butyric acid |
During the secondary or biological treatment of sewage water:
I. | The BOD of the wastewater gets reduced significantly. |
II. | The activated sludge contains aerobic micro-organisms that can clump together. |
III. | The entire activated sludge is pumped into anaerobic sludge digesters. |
1. Only I is correct
2. Only I and II are correct
3. I, II and III are correct
4. I, II and III are incorrect
Methanogens do not produce:
1. | oxygen | 2. | methane |
3. | hydrogen sulfide | 4. | carbon dioxide |
Which one of the following is not a nitrogen-fixing organism?
1. | Anabaena | 2. | Nostoc |
3. | Azotobacter | 4. | Pseudomonas |