Mark the incorrect option w.r.t chemosynthetic autotrophic bacteria

Options

A. (a) Hydrogenomonas and Beggiatoa
B. (b) Nitrococcus and Thiobacillus
C. (c) Nitrocystis and Leptothrix
D. (d) Chromatium and Thiospirillum

Answer

**Step-by-Step Solution:**

1. **Understanding Chemosynthetic Autotrophic Bacteria**:
- Chemosynthetic autotrophic bacteria are organisms that can produce their own food using chemical energy derived from inorganic substances. They do not rely on sunlight for energy, unlike photosynthetic organisms.

2. **Identifying Examples**:
- Common examples of chemosynthetic autotrophic bacteria include:
- Sulfur bacteria (e.g., Thiobacillus)
- Nitrogen-fixing bacteria (e.g., Nitrococcus, Nitrocystis)
- Methanogens (e.g., Methanobacterium)

3. **Analyzing the Options**:
- The question asks to identify the incorrect option regarding chemosynthetic autotrophic bacteria.
- Option A: Hydrogen monoxide (a methanogen) and Pegidua (a sulfur bacterium) - both are chemosynthetic.
- Option B: Bioaction (a nitrogen-fixing bacterium) and Nitrococcus (a nitrogen-fixing bacterium) - both are chemosynthetic.
- Option C: Nitrocystis (a nitrogen-fixing bacterium) and Leptothrix (a sulfur bacterium) - both are chemosynthetic.
- Option D: Chromatium and Thiospirilla - both are photoautotrophic bacteria, which means they use sunlight for energy.

4. **Identifying the Incorrect Option**:
- Since options A, B, and C all contain examples of chemosynthetic autotrophic bacteria, while option D contains examples of photoautotrophic bacteria, option D is the incorrect option.

5. **Conclusion**:
- Therefore, the answer to the question is option D, as it does not belong to the category of chemosynthetic autotrophic bacteria.

**Final Answer**: Option D

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