Which structure represents ear in amphibians and reptiles?

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the structure that represents the ear in amphibians and reptiles.

2. **Identifying External Ear Structures**: In humans, the external ear structure is known as the pinna, which is visible on the face. However, amphibians and reptiles do not have this external ear structure.

3. **Recognizing the Absence of External Structures**: Since amphibians and reptiles lack external ear structures, we need to identify what serves the function of the ear in these animals.

4. **Identifying the Ear Structure in Amphibians and Reptiles**: The structure that serves as the ear in amphibians and reptiles is called the tympanum.

5. **Conclusion**: Therefore, the structure that represents the ear in amphibians and reptiles is the tympanum.

**Final Answer**: The tympanum represents the ear in amphibians and reptiles.

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