Liver and pancreas of frog and rabbit are derived from :

Options

A. Ectoderm
B. Mesoderm
C. Endoderm
D. Both 1 and 3

Answer

To determine the embryonic origin of the liver and pancreas in frogs and rabbits, we need to analyze the three germ layers: ectoderm, mesoderm, and endoderm.

### Step-by-Step Solution:

1. **Understand the Germ Layers**:
- The three primary germ layers in embryonic development are ectoderm, mesoderm, and endoderm.
- **Ectoderm**: This is the outermost layer that forms the skin and nervous system.
- **Mesoderm**: This middle layer gives rise to muscles, bones, and the circulatory, excretory, and reproductive systems.
- **Endoderm**: The innermost layer that forms the lining of the digestive tract and associated organs.

2. **Identify the Organs in Question**:
- The liver and pancreas are both organs that are part of the digestive system.

3. **Determine the Origin of the Organs**:
- Since the liver and pancreas are involved in digestion, they are derived from the endoderm layer.

4. **Evaluate the Options**:
- **Option A (Ectoderm)**: Incorrect, as ectoderm does not form digestive organs.
- **Option B (Mesoderm)**: Incorrect, as mesoderm is responsible for other systems, not the digestive organs.
- **Option C (Endoderm)**: Correct, as the liver and pancreas originate from the endoderm.
- **Option D (Both 1 and 3)**: Incorrect, as only the endoderm is the source of these organs.

5. **Conclusion**:
- The liver and pancreas of frogs and rabbits are derived from the endoderm.

### Final Answer:
The liver and pancreas of frog and rabbit are derived from **endoderm**.

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