Which one of the following pairs is not correctly matched:

1. Serratia – Drug addiction

2. Spirulina – Single-cell protein

3. Rhizobium – Biofertilizer

4. Streptomyces – Antibiotic 

A major component of gobar gas is:

1. Methane

2. Ethane

3. Butane

4. Ammonia 

A free-living nitrogen-fixing cyanobacterium that can also form a symbiotic association with the water fern Azolla is:

1. Chlorella

2. Nostoc

3. Anabaena

4. Tolypothrix

Common indicator organism of water pollution is:

1. Eichhornia crassipes

2. Escherichia coli

3. Entamoeba histolytica

4. Lemna pancicostata 

Azolla is used in the cultivation of:

Which one produces gas by decomposing the gobar (Dung) in gobar gas:
1.  Fungus
2.  Virus
3.  Methanogenic bacteria
4.  Algae

Which bacteria is utilized in a Gobar gas plant:

1. Methanogens

2. Nitrifying bacteria

3. Ammonifying bacteria

4. Denitrifying bacteria

During the formation of bread it becomes porous due to the release of CO₂ by the action of:

Which of the following is used to manufacture ethanol from starch:

1. Penicillin

2. Saccharomyces

3. Azotobactor

4. Lactobacillus

Escherichia coli is used as an indicator organism to determine the pollution of water with:

1. Heavy metals

2. Faecal matter

3. Industrial effluents

4. Pollen of aquatic plants