Which one of the following is not a biofertilizer? 
1. Mycorrhiza
2. Agrobacterium
3. Rhizobium
4. Nostoc 

Which one of the following helps in the absorption of phosphorus from soil by plants?   
1. Anabaena
2. Glomus
3. Rhizobium
4. Frankia 

Read the following statement having two blanks (A and B):
“A drug used for _______ (A) ________ patients is obtained from a species of the organism _________ (B) _________.”
The one correct option for the two blanks is:         

Yeast is used in the production of   
1. Bread and beer.
2. Cheese and butter.
3. Citric acid and lactic acid.
4. Lipase and pectinase. 

Monascus purpureus is a yeast used commercially in the production of 

1. Citric acid
2. Blood cholesterol lowering statins
3. Ethanol
4. Streptokinase for removing clots from the blood vessels.

The domestic sewage in large cities  
1. When treated in STPs does not really require the aeration step as the sewage contains adequate oxygen.
2. Has very high amounts of suspended solids and dissolved salts.
3. Has a high BOD as it contains both aerobic and anaerobic bacteria.
4. Is processed by aerobic and then anaerobic bacteria in the secondary treatment in sewage treatment plants (STPs). 

A good producer of citric acid is 
1. Aspergillus
2. Pseudomonas
3. Clostridium
4. Saccharomyces 

What gases are produced in anaerobic sludge digesters?  

1. Methane and CO₂.
2. Methane, Hydrogen sulphide and CO₂.
3. Methane, Hydrogen sulphide and CO.
4. Hydrogen sulphide and CO₂. 

Match the following list of microbes and their importance.

    (a) (b) (c) (d)
1. (iii) (i) (iv) (ii)
2. (iii) (iv) (i) (ii)
3. (iv) (iii) (ii) (i)
4. (iv) (ii) (i) (iii)

Which of the following is wrongly matched in the given table?