Reptiles have large yolk-filled eggs having a special third membrane called ................

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the special third membrane found in reptile eggs.

2. **Understand Reptile Characteristics**: Reptiles are vertebrate animals characterized by dry, scaly skin and the ability to lay eggs. Their eggs are typically large and filled with yolk.

3. **Know the Types of Membranes**: Reptile eggs have four extra embryonic membranes: chorion, amnion, yolk sac, and allantois. Each of these membranes has a specific function.

4. **Focus on the Special Third Membrane**: Among these membranes, the amnion is identified as the special third membrane.

5. **Function of the Amnion**: The amnion forms a fluid-filled cavity that provides the embryo with its own internal aquatic environment. This adaptation allows reptiles to develop in a less water-dependent manner.

6. **Conclusion**: Therefore, the answer to the question is that the special third membrane in reptile eggs is called the **amnion**.

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