which of the following is not a function of conducting zone of respiratory track?

Options

A. conduction of air
B. clears the air of foreign particles
C. humidification of air
D. gaseous exchange

Answer

To determine which of the following is not a function of the conducting zone of the respiratory tract, we need to analyze the functions associated with the conducting zone.

### Step-by-Step Solution:

1. **Understanding the Conducting Zone**:
- The conducting zone of the respiratory tract includes structures such as the nasal cavity, pharynx, larynx, trachea, bronchi, and bronchioles. Its primary role is to transport air to the lungs.

2. **Identifying Functions of the Conducting Zone**:
- **Conduction of Air**: This is a primary function where air is conducted from the external environment into the lungs.
- **Clearing Air of Foreign Particles**: The conducting zone also plays a role in filtering and clearing the air of dust, pathogens, and other foreign particles through mechanisms like mucous secretion and ciliary action.
- **Humidification of Air**: The conducting zone helps to humidify the air, adding moisture to it before it reaches the lungs, which is essential for proper gas exchange.

3. **Identifying the Function Not Performed by the Conducting Zone**:
- **Gaseous Exchange**: This function occurs in the alveoli of the lungs, which are part of the respiratory zone, not the conducting zone. The conducting zone does not facilitate the exchange of oxygen and carbon dioxide.

4. **Conclusion**:
- Based on the analysis, the function that is not performed by the conducting zone of the respiratory tract is **gaseous exchange**.

### Final Answer:
The function that is not a part of the conducting zone of the respiratory tract is **gaseous exchange**.

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