NEETBotanyBiological Classification
A biologist observes an organism forming extensive blooms in a highly polluted water body. Upon further analysis, the organism is found to be a photosynthetic autotroph possessing chlorophyll a similar to green plants. Which of the following statements is true regarding this organism?
Options
- AIt belongs to Archaebacteria and possesses a different cell wall structure for survival in extreme conditions.
- BIt is a Eubacterium and some of its members possess specialised cells called heterocysts for nitrogen fixation
- CIt is a chemosynthetic autotroph that oxidises various inorganic substances to recycle nutrients.
- DIt is a methanogen that survives in aquatic environments and produces biogas.
Correct answer
B. It is a Eubacterium and some of its members possess specialised cells called heterocysts for nitrogen fixation
Step-by-step solution
The organism described forms blooms in polluted water bodies and possesses chlorophyll a similar to green plants. These features are characteristic of Cyanobacteria (blue-green algae). Cyanobacteria belong to the group Eubacteria (true bacteria). Some members of Cyanobacteria, such as Nostoc and Anabaena, have specialised cells called heterocysts that help in fixing atmospheric nitrogen. They are not Archaebacteria, nor are they chemosynthetic autotrophs (which oxidise inorganic substances) or methanogens (which ar