Which of the following statement is incorrect?

Options

A. Facecal accumulation in the rectum initiates a neural reflex causing an urge for its removal.
B. Reflex action for vomiting is controlled by medulla oblongata.
C. Irregular bowel movements cause constipation.
D. None of these

Answer

To determine which of the statements is incorrect, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze Statement A**:
- **Statement**: "Fecal accumulation in the rectum initiates a neural reflex."
- **Explanation**: When feces accumulate in the rectum, it causes rectal distention, which triggers the Rectoanal Inhibitory Reflex (RAIR). This reflex involves the relaxation of the internal anal sphincter, signaling the need to defecate.
- **Conclusion**: This statement is **correct**.

2. **Analyze Statement B**:
- **Statement**: "Reflex action for vomiting is controlled by medulla oblongata."
- **Explanation**: The vomit center is indeed located in the medulla oblongata, and it coordinates the physiological process of vomiting (emesis). The smooth muscles of the digestive tract contract and relax in a manner that leads to vomiting.
- **Conclusion**: This statement is **correct**.

3. **Analyze Statement C**:
- **Statement**: "Irregular bowel movements cause constipation."
- **Explanation**: Constipation is characterized by infrequent or difficult bowel movements. Irregular bowel movements can lead to a buildup of feces in the intestines, resulting in constipation.
- **Conclusion**: This statement is **correct**.

4. **Analyze Statement D**:
- **Statement**: "None of these is incorrect."
- **Explanation**: Since all the previous statements (A, B, and C) have been confirmed to be correct, this statement implies that there are no incorrect statements among the options provided.
- **Conclusion**: This statement is **correct**.

### Final Conclusion:
Since all the statements A, B, and C are correct, the answer to the question "Which of the following statement is incorrect?" is **option D: none of these**.

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