Microbes in Human Welfare

Probiotics are-

1. Cancer inducing microbes
2. New kind of food allergens
3. Live microbial food supplement
4. Safe antibiotics

Which one of the following pairs is wrongly matched ?

1. Methanogens – Gobar gas
2. Yeast – Ethanol
3. Streptomycetes – Antibiotic
4. Coliforms – Vinegar

Which one of the following statements is correct?

1. Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and potassium for plant nutrition in soil
2. Both Azotobacter and Rhizobium fix atmospheric nitrogen in root nodules of plants
3. At present it is not possible to grow maize without chemical fertilizers
4. Extensive use of chemical fertilizers may lead to eutrophication of nearby water bodies

Curing of tea leaves is brought about by the activity of

1. fungi
2. bacteria
3. mycorrhiza
4. viruses

For retting of jute the fermenting microbe used is

1. methanophilic bacteria
2. butyric acid bacteria
3. Helicobacter pylori
4. Streptococcus lactis.

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

1. Tolypothrix
2. Chlorella
3. Nostoc
4. Anabaena

Dough kept overnight in warm weather becomes soft and spongy because of :-

1. Cohesion
2. Absorption of carbon dioxide from atmosphere
3. Osmosis
4. Fermentation

Which one of the following pairs is not correctly matched ?

1. Spirulina – Single cell protein
2. Streptomyces – Antibiotic
3. Rhizobium – Biofertilizer
4. Serratia – Drug addiction

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