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O-LevelBiologyEcology & Environment5090/11 · Oct/Nov 2019 · Q301 Mark

Some bacteria survive best in waterlogged soils where they are able to obtain oxygen for respiration by breaking down nitrates. Nitrogen gas is released as a waste product. To which type of bacteria does this description apply?

Adecomposing bacteria
Bdenitrifying bacteria
Cnitrogen-fixing bacteria
Droot nodule bacteria

✓ Correct answer

B: denitrifying bacteria

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About this question

Topic
Ecology & Environment, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source
O-Level Biology, Oct/Nov 2019 Paper 1 Variant 1, question 30.

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