Q. Photosynthetic bacteria which help in nitrogen fixation is / are
I) Rhodospirillum
II) Azospirillum
III) Clostridium
IV) Chlorobacterium

 45  168 NTA AbhyasNTA Abhyas 2020 Report Error

Solution:

Rhodospirillum is non-sulphur bacteria that are anoxygenic photosynthetic. It also helps in nitrogen fixation by regulating nitrogenase enzyme activity. Chlorobacterium is also a photosynthetic bacterium that regulate nitrogen fixation with help of nitrification. Azospirillum is nitrogen-fixing bacteria but is non-photosynthetic. While Clostridium is photosynthetic but is not involved in nitrogen fixation.