Class XII · Biology practice

Microbes in Human Welfare MCQs

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455 questions in this collection · Page 13 of 46

Question 121 of 455
📘 CLASS XII

Microbes In Human Welfare

The floating cover of a biogas plant keeps on rising because:
A floating cover is placed over the slurry, which keeps on rising as the gas is produced in the tank due to the microbial activity.
Question 122 of 455
📘 CLASS XII

Microbes In Human Welfare

Why is the eradication of creatures often described as pests considered undesirable by organic farmers?
The eradication of the creatures that are often described as pests is undesirable, for without them the beneficial predatory and parasitic insects which depend upon them as food or hosts would not be able to survive.
Question 123 of 455
📘 CLASS XII

Microbes In Human Welfare

The use of biocontrol measures is strongly advocated because it greatly reduces our dependence on:
Thus, the use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.
Question 124 of 455
📘 CLASS XII

Microbes In Human Welfare

What does IPM stand for in the context of Baculovirus application?
This is especially desirable when beneficial insects are being conserved to aid in an overall integrated pest management (IPM) programme.
Question 125 of 455
📘 CLASS XII

Microbes In Human Welfare

Which bacterium is associated with the nitrogen fixation nodules on the roots of leguminous plants?
You have studied about the nodules on the roots of leguminous plants formed by the symbiotic association of Rhizobium.
Question 126 of 455
📘 CLASS XII

Microbes In Human Welfare

The increasing pressure to switch to organic farming is mainly a reaction against the overuse of:
We have now realised that there are problems associated with the overuse of chemical fertilisers and there is a large pressure to switch to organic farming.
Question 127 of 455
📘 CLASS XII

Microbes In Human Welfare

Which characteristic is NOT a benefit shown by plants having mycorrhizal associations?
Benefits include resistance to root-borne pathogens, tolerance to salinity and drought, and an overall increase in plant growth and development.
Question 128 of 455
📘 CLASS XII

Microbes In Human Welfare

Which metabolic pathway is inferred to take place in the dough used for dosa and idli, resulting in CO2 production?
The puffed-up appearance of dough is due to the production of CO2 gas, which is a result of fermentation by bacteria.
Question 129 of 455
📘 CLASS XII

Microbes In Human Welfare

In the classification of microbes, viruses, viroids, and prions are unique because they are only:
The text mentions asking which organisms are only microscopic. Viruses, viroids, and prions fit this description.
Question 130 of 455
📘 CLASS XII

Microbes In Human Welfare

The major contribution of microbes discussed in the chapter includes their role in:
The chapter discusses contributions in household products, industrial products (including beverages and antibiotics), sewage treatment, biogas, biocontrol, and biofertilisers.
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