Pavlov's pouch is

Options

A. An artificial stomach
B. A bag containing digestive enzymes
C. A bag containing food
D. Opened stomach of a dog.

Answer

**Step-by-Step Solution:**

1. **Understanding Pavlov's Pouch**: Pavlov's pouch is a term associated with an experimental setup created by the physiologist Ivan Petrovich Pavlov. It is important to note that this pouch is not a naturally occurring structure but rather an artificially created one.

2. **Purpose of Pavlov's Pouch**: The primary purpose of creating Pavlov's pouch was to study the physiology of the digestive tract. This involved examining how the stomach functions and how it secretes digestive enzymes and acids.

3. **Description of Pavlov's Pouch**: Specifically, Pavlov's pouch refers to a small portion of the stomach that was surgically separated from the main stomach of a dog. This allowed researchers to observe the digestive processes in a controlled environment.

4. **Analyzing the Options**:
- **Option 1**: An artificial stomach - This is incorrect because Pavlov's pouch is not a complete stomach but a part of it.
- **Option 2**: A bag containing digestive enzymes - This is also incorrect as it does not accurately describe Pavlov's pouch.
- **Option 3**: A bag containing food - This is incorrect as well; Pavlov's pouch is not merely a container for food.
- **Option 4**: An open stomach of a dog - This is the correct answer, as Pavlov's pouch is indeed a part of the stomach that was exposed for study.

5. **Conclusion**: Therefore, the correct answer to the question "Pavlov's pouch is" is **an open stomach of a dog**.

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