Gaseous exchange occur in birds inside

Options

A. Air capillaries
B. Air sacs
C. Bronchi
D. Sacchobronchi.

Answer

**Step-by-Step Solution:**

1. **Identify the Respiratory Organs in Birds:**
- Birds have specialized respiratory organs, primarily the lungs, which are responsible for gas exchange.

2. **Understand the Role of Air Sacs:**
- In addition to the lungs, birds possess air sacs that play a crucial role in their respiratory system. These air sacs facilitate the movement of air through the lungs and are essential for efficient gas exchange.

3. **Number and Location of Air Sacs:**
- Depending on the species, birds typically have about 7 to 9 air sacs. These air sacs are strategically located and can extend into various bones, including the humerus (the upper arm bone), femur (the thigh bone), and vertebrae.

4. **Pneumatic Bones:**
- The bones of birds are known as pneumatic bones, which means they are lighter and contain air spaces instead of bone marrow. This adaptation helps reduce the overall weight of the bird, making flight easier.

5. **Conclusion:**
- The correct answer to the question is that gaseous exchange in birds occurs inside the air sacs. These structures are vital for the bird's respiratory efficiency and overall flight capability.

**Final Answer:**
Gaseous exchange occurs in birds inside the air sacs.

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