Chemolithotrophs are those bacteria which can utilize

Options

A. Inorganic material as the energy source
B. Light as the energy source
C. Organic compound as the electron source
D. Crude oil as carbon source

Answer

**Step-by-Step Solution:**

1. **Understanding Chemolithotrophs**: Chemolithotrophs are a specific group of bacteria that derive their energy from the oxidation of inorganic compounds.

2. **Identifying Modes of Nutrition**: Bacteria can be categorized based on their nutritional modes into autotrophic and heterotrophic. Chemolithotrophs fall under the autotrophic category, specifically the chemoautotrophic type.

3. **Energy Sources for Chemolithotrophs**: Chemolithotrophs utilize reduced inorganic materials as their primary energy source. This means they can oxidize inorganic substances to obtain energy necessary for their growth.

4. **Examples of Inorganic Materials**: Common inorganic materials that chemolithotrophs can utilize include:
- Hydrogen (H2)
- Hydrogen sulfide (H2S)
- Reduced metals (e.g., iron)
- Carbon dioxide (CO2) can also be used as a carbon source but is not the energy source.

5. **Elimination of Incorrect Options**:
- Light as an energy source is associated with photoautotrophs, not chemolithotrophs.
- Organic compounds are typically used by heterotrophs, not chemolithotrophs.
- Crude oil, being an organic compound, is also not a source for chemolithotrophs.

6. **Conclusion**: The correct answer to the question is that chemolithotrophs utilize inorganic materials as their energy source.

**Final Answer**: Chemolithotrophs are those bacteria which can utilize inorganic materials as their energy source.

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