Chemoautotrophs derive their energy from

Options

A. Sun
B. Inorganic chemicals
C. Dead organisms
D. Living organisms

Answer

**Step-by-Step Solution:**

1. **Understanding Chemoautotrophs**: Chemoautotrophs are a type of organism that can produce their own food using inorganic substances. Unlike photoautotrophs, which use sunlight for energy, chemoautotrophs derive their energy from chemical reactions involving inorganic molecules.

2. **Energy Source**: The primary source of energy for chemoautotrophs comes from inorganic chemicals. This includes substances like hydrogen sulfide, ammonia, nitrites, and ferrous iron. These chemicals are oxidized to release energy, which is then used to convert carbon dioxide into organic compounds.

3. **Examples of Chemoautotrophs**: Common examples of chemoautotrophic bacteria include nitrifying bacteria (which oxidize ammonia to nitrites), sulfur-oxidizing bacteria (which oxidize hydrogen sulfide to sulfur), and iron-oxidizing bacteria (which oxidize ferrous iron to ferric iron).

4. **Distinguishing from Other Organisms**: It’s important to differentiate chemoautotrophs from other types of bacteria. For instance, saprophytic bacteria feed on dead organic matter, while parasitic bacteria derive nutrients from living hosts. Chemoautotrophs do not fit into these categories as they rely solely on inorganic substances for their energy.

5. **Conclusion**: Therefore, the correct answer to the question "Chemoautotrophs derive their energy from" is "inorganic chemicals."

**Final Answer**: Chemoautotrophs derive their energy from inorganic chemicals.

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