Microbes in Human Welfare

A major component of gobar gas is

1. ethane
2. methane
3. butane
4. ammonia

Which of the following plants are used as green manure in crop fields and in sandy soils ?

1. Calotropis procera and Phyllanthus niruri
2. Dichanthium annulatum and Azolla nilotica
3. Saccharum munja and Lantana camara
4. Crotalaria juncea and Alhagi camelorum

During anaerobic digestion of organic waste, such as in producing biogas, which one of the following is left undegraded :-

1. Lignin
2. Cellulose
3. Hemi-cellulose
4. Lipids

Which bacteria is utilized in Gobar gas plant ?

1. Nitrifying bacteria
2. Methanogens
3. Ammonifying bacteria
4. Denitrifying bacteria

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

1. Protozoans
2. Bacteria
3. Yeast
4. Virus

Which of the following is a true pair of biofertilizers?

1. Nostoc and legume
2. Rhizobium and grasses
3. Salmonella and E. coli
4. Azolla and BGA

Which aquatic fern performs nitrogen fixation?

1. Azolla
2. Nostoc
3. Salvia
4. Salvinia

What is B.O.D.?

1. The total amount of O2 present in water
2. The amount of O2 utilised by organisms in water
3. The amount of O2 utilised by microorganisms for decomposition
4. All of the above

Which aquatic fern is used to increase the yield in paddy crop?

1. Salvinia
2. Isoetes
3. Marsilea
4. Azolla

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

1. Saccharomyces
2. Lactobacillus
3. Azotobacter
4. Penicillium