Which of the following is NOT a component of all hollow tube regions of the gut? Mucosa Muscularis externa Mesentary Adventitia Submucosa

To determine which option is NOT a component of all hollow tube regions of the gut, let's analyze each term in the context of gastrointestinal anatomy.

1. Mucosa: This is the innermost layer of the gut that comes into direct contact with the contents of the digestive tract. It is present in all hollow tube regions.

2. Muscularis externa: This layer is responsible for peristalsis and is present in all regions of the gut, aiding in the movement of food.

3. Submucosa: This layer contains blood vessels, nerves, and connective tissue, and it is also present across all hollow parts of the gut.

4. Adventitia: This outer layer is present in parts of the gut that are not covered by peritoneum (the abdominal cavity lining). However, in areas like the stomach and intestines, a different covering called the serosa is present.

5. Mesentery: This is not a layer of the gut wall but a fold of tissue that attaches the intestines to the abdominal wall and contains blood vessels, nerves, and lymphatics. It is not found universally in all hollow tube regions.

Conclusion

The correct answer is Mesentery as it is not a layer of the gut wall but rather a supportive structure associated with certain parts of the GI tract.