Which of these parts of the brainstem is correctly matched with its main function ?

Options

A. ventral respiratory groups stimulate the diaphragm contraction
B. dorsal respiratory groups limit inflation of the lungs
C. pontine respiratory group switch between inspiration and expiration
D. all of the above

Answer

To solve the question regarding which part of the brainstem is correctly matched with its main function, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Brainstem**:
- The brainstem connects the spinal cord to the forebrain and consists of three main parts: the midbrain, the pons, and the medulla oblongata.

2. **Identify the Groups in the Medulla Oblongata**:
- The medulla oblongata contains two respiratory groups:
- Dorsal Respiratory Group (DRG)
- Ventral Respiratory Group (VRG)

3. **Examine the Functions of Each Group**:
- **Dorsal Respiratory Group (DRG)**: Primarily responsible for stimulating the diaphragm and external intercostal muscles, which facilitate inspiration (breathing in).
- **Ventral Respiratory Group (VRG)**: Responsible for stimulating expiratory movements (breathing out).
- **Pontine Respiratory Group**: Located in the pons, it helps regulate the rhythm of breathing, switching between inspiration and expiration.

4. **Analyze the Options Given**:
- **Option A**: Ventral respiratory group stimulates diaphragm contraction. (Incorrect, as this is the function of the DRG)
- **Option B**: Dorsal respiratory group limits inflation of the lungs. (Incorrect, as the DRG stimulates diaphragm contraction)
- **Option C**: Spontaneous respiratory group switches between inspiration and expiration. (Correct, as this describes the function of the pontine respiratory group)
- **Option D**: All of the above. (Incorrect, since options A and B are wrong)

5. **Conclusion**:
- The correct answer is **Option C**: Spontaneous respiratory group switches between inspiration and expiration.