Which group of animals have spiracles and tracheae for breathing and respiration ?

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks which group of animals possesses spiracles and tracheae for breathing and respiration.

2. **Identifying the Key Terms**:
- Spiracles: These are small openings on the surface of certain animals that allow air to enter.
- Tracheae: These are branching tubes that transport air within the body.

3. **Recognizing the Group of Animals**: The group of animals that have spiracles and tracheae is **Insects**.

4. **Explaining the Function**: Insects utilize a specialized respiratory system known as the tracheal system. This system is highly efficient for gas exchange, allowing oxygen to enter and carbon dioxide to exit.

5. **Describing the Structure**:
- The tracheae are lined with epithelial cells and have spiral ridges called tracheal intima, which help maintain their structure.
- Spiracles are the external openings through which air enters the tracheal system.

6. **Conclusion**: Therefore, the answer to the question is that **Insects** are the group of animals that have spiracles and tracheae for breathing and respiration.

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