Name the waste product excreted :
by the lungs.

Answer

**Step-by-Step Solution:**

1. **Identify the Function of the Lungs**: The lungs are primarily responsible for respiration in humans. They facilitate the exchange of gases, which is essential for maintaining life.

2. **Understand the Gas Exchange Process**: During respiration, the lungs take in oxygen from the atmosphere and release carbon dioxide produced by the body's cells. This process is crucial for providing oxygen to the body and removing waste gases.

3. **Identify the Waste Product**: Among the gases exchanged, carbon dioxide (CO2) is produced as a waste product by the cells of the body.

4. **Conclude the Answer**: Since the lungs are responsible for expelling this waste product, the waste product excreted by the lungs is carbon dioxide.

**Final Answer**: The waste product excreted by the lungs is carbon dioxide (CO2).

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