Home › Previous year questions › GATE 2021 ES › Question 45GATE 2021 ES – Question 45 Environmental Microbiology · Microbial Metabolism · 2 marks · Multiple select
Select correct statements about Nitrobacter nitrifying bacteria.
They are autotrophs They are eukaryotes They use mitochondria to convert chemical to cellular energy They convert nitrate to nitrite Practise this question in The GATE Grind →
Show answer and explanation Correct answer: (A) They are autotrophs
Explanation Nitrobacter are prokaryotic chemolithoautotrophs:they obtain energy by oxidizing nitrite to nitrate and fix carbon. Thus **A**. They lack mitochondria, and D reverses their characteristic nitrification reaction. This distinguishes them from ammonia oxidizers and denitrifiers.
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