The reaction involving breaking of complex compounds into simpler ones is called

Options

A. anabolism
B. homeostasis
C. metabolism
D. catabolism

Answer

To answer the question, "The reaction involving breaking of complex compounds into simpler ones is called," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Metabolism**:
- Metabolism refers to the sum total of all chemical reactions occurring in a living organism. It includes both the breakdown and synthesis of compounds.

2. **Identifying Types of Metabolism**:
- Metabolism can be divided into two main types:
- **Catabolism**: This is the process of breaking down complex molecules into simpler ones, releasing energy in the process.
- **Anabolism**: This is the opposite process where simpler molecules are combined to form complex molecules, requiring energy.

3. **Focusing on the Breakdown Process**:
- The question specifically asks for the reaction that involves breaking down complex compounds. This clearly aligns with the definition of catabolism.

4. **Examples of Catabolic Reactions**:
- A common example of a catabolic reaction is glycolysis, where glucose (a six-carbon molecule) is broken down into pyruvate (a three-carbon molecule), and further into carbon dioxide and energy during the Krebs cycle.

5. **Conclusion**:
- Therefore, the correct term for the reaction involving the breakdown of complex compounds into simpler ones is **catabolism**.

### Final Answer:
The reaction involving breaking of complex compounds into simpler ones is called **catabolism**.

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