Secondary sewage treatment is mainly a

(1) mechanical process

(2) chemical process

(3) biological process

(4) physical process

Select the correct statement from the following

(1) Biogas is produced by the activity of aerobic bacteria on animal waste

(2) Methanobacterium is an aerobic bacterium found in rumen of cattle.

(3) Biogas, commonly called gobar gas, is pure methane

(4) Activated sludge-sediment in settlement tanks of sewage treatment plant is a right source of aerobic bacteria

A common biocontrol agent for the control of plant disease is 

(1) Baculovirus

(2) Bacillus thuringiensis

(3) Glomus

(d) Trichoderma

Which of the following is not used as a biopesticide?

(1) Bacillus thuringiensis

(2) Trichoderma harzianum

(3) Nuclear Polyhedrosis Virus (NPV)

(4) Xanthomonas campestris

A compound which is produced by an organism that inhibits growth of other organism is

called:

1. xenobiotics                         

2. antibiotic

3. antibody                             

4. interferon

Select the correct statement

(1) Acetobacter aceti produces citric acid.

(2) Saccharomyces cerevisiae is used as clot buster

(3) Penicillium notanum restrict the growth of Staphylococci

(4) Methanogens are found in aerobic conditions.

Which of the following statements is incorrect regarding fermentation ?

1. Propionibacterium is used to ferment the cheese.

2. The puffed-up appearance of dough is due to the production of $C{O}_2$ gas. 

3. Fermentation in muscle produces ethanol.

4. Toddy is made by fermenting sap from palms.

Which of the following statements is correct?

Select the correct pair of microorganism and the product obtained from it.

(1) Monascus purpureus - produces large holes in Swiss cheese.

(2) Saccharomyces cerevisiae - used for making wine and beer after distillation

(3) Streptococuss-produces streptokinase which is used to remove clots.

(4) Aspergillus niger - produces citric acid and butyric acid.

Select the incorrect match

(1) Citric acid - Aspergillus niger

(2) Streptokinase - Streptococcus

(3) Butyric acid - Clostridium acetobutylicum

(4) Cyclosporin-A - Monascus purpures