Which part of human respiratory system provides surface for exchange of gases?

Alveoli

The correct answer is Option (4)- Alveoli

The part of the human respiratory system that provides a surface for the exchange of gases is the Alveoli.

Alveoli:

• Alveoli are tiny, air-filled sacs located at the ends of the bronchioles in the lungs.
• These structures are the primary sites for gas exchange between the respiratory system and the circulatory system (blood).
• Oxygen from the inhaled air diffuses across the alveolar walls into the bloodstream, and carbon dioxide, a waste product, diffuses from the blood into the alveoli to be exhaled.

While the other components of the respiratory system, such as bronchi, trachea, and bronchioles, play crucial roles in conducting air to and from the lungs, it is the alveoli where the actual exchange of oxygen and carbon dioxide occurs, facilitating respiratory gas exchange.