Which one protects the lungs?

Options

A. Ribs
B. Vertebral column
C. Sternum
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Identify the Organs Involved**: The lungs are the main respiratory organs in the human body. They are responsible for gas exchange, allowing oxygen to enter the bloodstream and carbon dioxide to be expelled.

2. **Understand the Structure of the Lungs**: Humans have two lungs - the left lung and the right lung. The left lung has two lobes, while the right lung has three lobes. This anatomical difference is important but does not directly relate to the protection of the lungs.

3. **Identify Protective Structures**: The lungs are protected by several structures:
- **Ribs**: There are 12 pairs of ribs that form a cage around the lungs, providing lateral protection.
- **Vertebral Column**: This is located at the back (dorsal side) and provides protection from the rear.
- **Sternum**: This flat bone is located at the front (ventral side) and protects the lungs from the front.

4. **Conclusion**: All of these structures (ribs, vertebral column, and sternum) work together to protect the lungs from physical damage and external threats.

5. **Final Answer**: Therefore, the correct answer to the question "Which one protects the lungs?" is that all of the above structures (ribs, vertebral column, and sternum) protect the lungs.

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