Respiration mechanism is controlled by

Options

A. Central nervous system
B. Sympathetic nervous system
C. Parasympathetic nervous system
D. Autonomic nervous system.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the control mechanism of respiration in the body. This involves identifying the part of the nervous system responsible for regulating breathing.

2. **Identifying Key Components**:
- There are different systems in the body that can influence respiration: the central nervous system (CNS), sympathetic nervous system, parasympathetic nervous system, and autonomic nervous system.
- It's important to distinguish between voluntary and involuntary control of respiration.

3. **Role of the Central Nervous System**:
- The central nervous system, which includes the brain and spinal cord, plays a crucial role in controlling respiration.
- The respiration center is located in the medulla oblongata, which is part of the brainstem.

4. **Involuntary vs. Voluntary Respiration**:
- Involuntary respiration is regulated by the upper brainstem, particularly the pons, which controls the rate of breathing.
- Voluntary respiration is primarily controlled by the medulla oblongata, which sends signals to the respiratory muscles to facilitate breathing.

5. **Conclusion**: Both voluntary and involuntary aspects of respiration are governed by the central nervous system. Therefore, the correct answer to the question is the **Central Nervous System (CNS)**.

**Final Answer**: The respiration mechanism is controlled by the Central Nervous System (CNS).

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