___________ is the process in which energy is released in living organisms.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the process through which energy is released in living organisms.

2. **Identifying the Process**: The process that releases energy in living organisms is known as respiration.

3. **Explaining Respiration**: Respiration is a metabolic process that occurs in all living organisms. It involves the breakdown of glucose in the presence of oxygen to produce energy in the form of ATP (adenosine triphosphate).

4. **Importance of Respiration**: All living organisms require energy to survive, and respiration is essential for providing this energy. Without respiration, an organism cannot live.

5. **Biochemical Nature of Respiration**: Respiration is a biochemical process that involves various enzymes and catalysts to facilitate the breakdown of glucose.

6. **Distinction from Breathing**: It is important to differentiate respiration from breathing. Breathing refers to the physical act of inhaling and exhaling gases, while respiration is a chemical process that produces energy.

7. **Conclusion**: Therefore, the answer to the question is "Respiration."

**Final Answer**: Respiration is the process in which energy is released in living organisms.

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