Pneumotaxic center which can moderate the functions of the respiratory rhythm center is present in

Options

A. pons region of brain
B. thalamus
C. spinal cord
D. right cerebral hemisphere.

Explanation

To answer the question regarding the location of the pneumotaxic center, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Pneumotaxic Center**:
- The pneumotaxic center is a neural structure that plays a crucial role in regulating the respiratory rhythm. It provides inhibitory impulses that help control the duration of inspiration, thereby preventing excessive lung distention.

2. **Function of the Pneumotaxic Center**:
- Its primary function is to moderate the functions of the respiratory rhythm center. By inhibiting inspiration, it helps maintain a balanced cycle of inspiration and expiration.

3. **Location in the Brain**:
- The pneumotaxic center is located in the hindbrain. The hindbrain consists of three main parts: the pons, cerebellum, and medulla oblongata.

4. **Identifying the Specific Region**:
- Within the hindbrain, the pneumotaxic center is specifically found in the pons. More precisely, it is located on the dorsal side of the pons, which is referred to as the "pons varolii."

5. **Evaluating the Options**:
- Given the options provided (pons region, thalamus, spinal cord, right cerebral hemisphere), we can conclude that the correct answer is the pons region of the brain.

### Final Answer:
The pneumotaxic center, which can moderate the functions of the respiratory rhythm center, is present in the **pons region of the brain**.

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