Q. Which among the following factors are limiting growth of phytoplankton organisms?

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Q. Which among the following oceans is the most richest in life?

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Q. In which of the following water bodies, fertility is high?

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Q. Which of the following product is not obtained from dissimilation of organic matter under aerobic conditions?

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Q. Which of the following organism have siliceous skeletons?

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Q. The nonsymbiotic bacteria which fix nitrogen live in the soil independently are

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Q. Nitrogen fixation by the microorganisms can be detected by adopting the approach of

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Q. Which of the following is not the biofertilisers producing bacteria?

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Q. Which of the following is capable of oxidizing sulfur to sulfates?

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Q. Most soil protozoa are flagellates or amoebas, having their dominant mode of nitrogen as

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Q. Which of the following microorganism use H2S as the electron donor to reduce carbon dioxide?

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Q. Nitrifying bacteria can not be isolated directly by the usual techniques employed to isolate hetrotrophic bacteria. The reasons may be due to

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Q. Bacteria, as a group, are responsible for

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Q. The phenomenon of commensalism refers to a relationship between organisms in which

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Q. The population of algae in soil is __________ that of either bacteria or fungi.

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Q. The transformation of nitrates to gaseous nitrogen is accomplished by microorganisms in a series of biochemical reactions. The process is known as

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Q. Nitrogen fixation refers to the direct conversion of atmospheric nitrogen gas into

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Q. The diagnostic enzyme for denitrification is

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Q. A heterocyst is

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Q. The groups of symbiotic bacteria, which have the ability to fix nitrogen

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