Sphincter of Oddi guards

Options

A. Hepato-pancreatic duct
B. Common bile duct
C. Pancreatic duct
D. Cystic duct

Answer

To solve the question regarding what the Sphincter of Oddi guards, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Sphincter of Oddi**: The Sphincter of Oddi is a muscular valve located at the junction where the bile duct and pancreatic duct meet before they enter the duodenum.

2. **Identify its Function**: The primary function of the Sphincter of Oddi is to regulate the flow of bile and pancreatic juices into the duodenum. It opens to allow these digestive juices to flow and closes to prevent backflow.

3. **Analyze the Options**:
- **Hepatopancreatic duct**: This is the duct formed by the convergence of the common bile duct and the pancreatic duct. The Sphincter of Oddi guards this duct.
- **Common bile duct**: This duct carries bile from the liver and gallbladder to the duodenum but is not specifically guarded by the Sphincter of Oddi.
- **Pancreatic duct**: This duct carries pancreatic juices but is also not specifically guarded by the Sphincter of Oddi.
- **Cystic duct**: This duct connects the gallbladder to the common bile duct and is not associated with the Sphincter of Oddi.

4. **Conclusion**: Based on the function and location of the Sphincter of Oddi, the correct answer is that it guards the **Hepatopancreatic duct**.

### Final Answer:
The Sphincter of Oddi guards the **Hepatopancreatic duct**.

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