Final answer:
The respiratory system is divided into the upper and lower respiratory tracts, with the upper part including structures like the nose and pharynx for air filtration, while the lower part consists of the trachea and lungs for gas exchange.
Step-by-step explanation:
The respiratory system is organized into two main regions: the upper respiratory tract and the lower respiratory tract. The upper respiratory tract includes structures such as the nose, nasal cavity, sinuses, pharynx, and larynx, all of which are responsible for filtering, warming, and moistening air as it enters the body. The lower respiratory tract consists of the trachea, bronchi, bronchioles, and alveoli, primarily involved in gas exchange with the blood. The upper respiratory tract serves as a passageway for air, providing a route between the outside atmosphere and the lungs.
It also serves to clean, humidify, and warm the incoming air, ensuring it is suitable for the delicate tissues of the respiratory system. However, no gas exchange takes place in these upper organs. On the other hand, the lower respiratory tract carries air to the site of gas exchange in the alveoli, where oxygen is provided for use by the body’s cells, and carbon dioxide is removed from the bloodstream to be exhaled.