What is the function of respiratory part of human
respiratory system?

Options

A. It clears the incoming air from foreign particles
B. It brings the temperature of air upto the body
temperature
C. It transports the atmospheric air
D. It exchanges `O_(2)` and `CO_(2)` between blood and
atmospheric air

Answer

### Step-by-Step Solution:

1. **Identify the Components of the Respiratory System**:
- The respiratory part of the human respiratory system includes structures such as the mouth, throat, pharynx, larynx, trachea, and bronchi.

2. **Understand the Main Function**:
- The primary function of the respiratory part is to facilitate the exchange of gases, specifically oxygen and carbon dioxide, between the blood and the atmospheric air.

3. **Air Conditioning**:
- The respiratory system also plays a role in conditioning the incoming air. This includes warming the air to body temperature and humidifying it to prevent damage to the respiratory tissues.

4. **Clearing Foreign Particles**:
- Another important function is to filter and clear the incoming air from foreign particles, such as dust and pathogens, which helps protect the lungs and overall respiratory health.

5. **Summarize the Functions**:
- In summary, the functions of the respiratory part of the human respiratory system include:
- Gas exchange (oxygen and carbon dioxide)
- Conditioning of air (warming and humidifying)
- Clearing of foreign particles from the air

### Final Answer:
The function of the respiratory part of the human respiratory system is primarily to facilitate the exchange of oxygen and carbon dioxide between the blood and atmospheric air, while also conditioning the air and clearing it of foreign particles.

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