During which stage of the sewage treatment are the microbes used?

1.	Primary	2.	Secondary
3.	Tertiary	4.	Quaternary

Biogas is a mixture of:

A biological control being developed for use in the treatment of plant diseases is the fungus:

‘Toddy’, a traditional drink of some parts in southern India, is made by fermenting sap from:

The ‘Roquefort cheese’ is ripened by:

With reference to human beings, antibiotics are actually:

Which of the following human diseases cannot be treated by antibiotics?

“Clearing” of fruit juices in industrial preparations is achieved by the action of enzyme:

The figure shows two parameters that can be used as a measure of pollution levels in sewage water. The red and blue color shows the change in the levels of these parameters during sewage water treatment. A and B respectively can be:

In the secondary treatment or biological treatment of sewage water, the primary effluent is passed into large aeration tanks where it is constantly agitated mechanically and the air is pumped into it. This allows:
1. vigorous growth of useful aerobic microbes into flocs
2. the decrease in the number of aerobes in the water
3. rapid increase in the count of methanogens
4. a dramatic decrease in the anaerobic methanogens