Class XII · Biology practice

Microbes in Human Welfare MCQs

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455 questions in this collection · Page 37 of 46

Question 361 of 455
📘 CLASS XII

Microbes In Human Welfare

The process of physical removal of large and small particles from sewage is known as _____ treatment.
Primary treatment steps basically involve physical removal of particles—large and small—from the sewage.
Question 362 of 455
📘 CLASS XII

Microbes In Human Welfare

The formation of the primary sludge occurs during the process of _____ in the primary treatment tank.
All solids that settle form the primary sludge.
Question 363 of 455
📘 CLASS XII

Microbes In Human Welfare

The volume of oxygen that would be consumed to oxidize all organic matter in one liter of water by bacteria is known as _____.
BOD refers to the amount of the oxygen that would be consumed if all the organic matter in one liter of water were oxidised by bacteria.
Question 364 of 455
📘 CLASS XII

Microbes In Human Welfare

Anaerobic sludge digesters facilitate the production of biogas, which is primarily composed of methane, CO2, and _____.
Bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide.
Question 365 of 455
📘 CLASS XII

Microbes In Human Welfare

The use of biogas produced in rural areas is primarily for cooking and _____.
The biogas thus produced is used for cooking and lighting.
Question 366 of 455
📘 CLASS XII

Microbes In Human Welfare

The philosophy of the organic farmer is a holistic approach, aiming to develop an understanding of the complex webs of interaction between organisms that constitute the field fauna and _____.
This is a holistic approach that seeks to develop an understanding of the webs of interaction between the myriad of organisms that constitute the field fauna and flora.
Question 367 of 455
📘 CLASS XII

Microbes In Human Welfare

The development of methods of genetic engineering allowed scientists to introduce the B. thuringiensis toxin genes into _____.
The scientists have introduced B. thuringiensis toxin genes into plants.
Question 368 of 455
📘 CLASS XII

Microbes In Human Welfare

Baculoviruses are pathogens that specifically attack insects and other _____.
Baculoviruses are pathogens that attack insects and other arthropods.
Question 369 of 455
📘 CLASS XII

Microbes In Human Welfare

The symbiotic association Rhizobium forms with leguminous plants results in the formation of _____.
You have studied about the nodules on the roots of leguminous plants formed by the symbiotic association of Rhizobium.
Question 370 of 455
📘 CLASS XII

Microbes In Human Welfare

The fungal symbiont in mycorrhizal associations provides the plant with _____ from the soil.
The fungal symbiont... absorbs phosphorus from soil and passes it to the plant.
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