Book lungs are respiratory structures of

Options

A. Arthropoda
B. Mollusca
C. Mammals
D. Earthworm

Answer

**Step-by-Step Solution:**

1. **Understanding Book Lungs**: Book lungs are specialized respiratory structures that facilitate gas exchange in certain organisms. They are named for their appearance, which resembles the pages of a book.

2. **Identifying the Group**: Book lungs are primarily found in a specific group of animals known as arachnids. This group includes creatures such as spiders and scorpions.

3. **Function of Book Lungs**: The primary function of book lungs is to allow for the exchange of gases (oxygen and carbon dioxide) between the organism and the environment. This is crucial for respiration.

4. **Structure of Book Lungs**: The structure of book lungs consists of thin, flat layers (lamellae) that are stacked together, creating a large surface area for gas exchange. Blood flows between these layers to facilitate the transfer of gases.

5. **Conclusion**: Therefore, book lungs are respiratory structures found in arachnids, such as spiders and scorpions, and they play a vital role in the respiration process.

**Final Answer**: Book lungs are respiratory structures of arachnids (e.g., spiders and scorpions).

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