Microbes in Human Welfare

Which of the following is mainly produced by the activity of anaerobic bacteria on sewage ?

1. Propane
2. Mustard gas
3. Marsh gas
4. Laughing gas

An organism used as a Biofertilizer for raising soyabean crop is :

1. Azotobacter
2. Azospirillum
3. Nostoc
4. Rhizobium

Ethanol is commercially produced through a particular species of :

1. Clostridium
2. Trichoderma
3. Aspergillus
4. Saccharomyces

Continuous addition of sugars in 'fed batch' fermentation is done to :

1. obtain antibiotics
2. produce methane
3. purify enzymes
4. degrade sewage

Organisms called Methanogens are most abundant in a :

1. Polluted stream
2. Hot spring
3. Cattle yard
4. Sulphur rock

Which one of the following helps in absorption of phosphorus from soil by plants?

1. Glomus
2. Rhizobium
3. Frankia
4. Anabaena

An example of endomycorrhiza is -

1. Nostoc
2. Rhizobium
3. Glomus
4. Agaricus

Select the correct statement from the following:

1. Methanobacterium is an aerobic bacterium found in rumen of cattle
2. Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria
3. Biogas, commonly called gobar gas, is pure methane
4. Biogas is produced by the activity of aerobic bacteria on animal waste

A common biocontrol agent for the control of plant diseases is –

1. Bacillus thuringiensis
2. Trichoderma
3. Glomus
4. Baculovirus

The common nitrogen-fixer in paddy fields is –

1. Azospirillum
2. Frankia
3. Rhizobium
4. Oscillatoria