The residue left after methane production from cattle dung is:

1. burnt

2. burried in land fills

3. used as manure

4. used in civil construction

Gases found in biogas are:
1. Carbon dioxide is the only gas
2. Methane is the only gas
3. Carbon dioxide, hydrogen sulphide and Methane
4. Carbon dioxide, hydrogen cyanide and Methane

In the given diagram the gas X can be :

1. Hydrogen

2. Carbon monoxide

3. Ammonia

4. Oxygen

Which of the following microbes is correctly paired with its function ?

(1) Aspergillus niger - Production of lactic acid

(2) Trichoderma polysporum  - Lowers blood cholesterol

(3) Saccharomyces cerevisiae  - Production of citric acid

(4) Methanogenic bacteria - Gobar gas formation 

Methanogens are found in:

A. Ethanol

B. Organic acids

C. Anaerobic sludge

D. Rumen of cattle

(1) A, C, D

(2) C, D

(3) B, C, D

(4) A, B