What is one function of the nostrils and nasal cavity in respiration?

What is one function of the nostrils and nasal cavity in respiration?

• A. Gas exchange occurs in the nasal cavity.
• B. Humidifies air and filters particles.
• C. It stores air for later use.
• D. It participates in vocalization.

Answer: (B)

The nasal cavity conditions the air before it reaches the lungs. It humidifies and warms incoming air to near body temperature, which protects the delicate tissues of the airways and helps keep mucous membranes functioning well. The lining also traps dust, microbes, and other particles in mucus, and the cilia sweep that mucus toward the throat to be swallowed, preventing irritants from reaching the lower respiratory tract. Gas exchange happens later in the alveoli of the lungs, not in the nasal cavity, so storing air is not a function here. While the nose can influence voice resonance, its primary role during respiration is to humidify and filter the air.

The nasal cavity conditions the air before it reaches the lungs. It humidifies and warms incoming air to near body temperature, which protects the delicate tissues of the airways and helps keep mucous membranes functioning well. The lining also traps dust, microbes, and other particles in mucus, and the cilia sweep that mucus toward the throat to be swallowed, preventing irritants from reaching the lower respiratory tract. Gas exchange happens later in the alveoli of the lungs, not in the nasal cavity, so storing air is not a function here. While the nose can influence voice resonance, its primary role during respiration is to humidify and filter the air.