Respiratory system (English)

The respiratory system can be divided into two parts; the upper respiratory tract and the lower respiratory tract. The upper respiratory tract consists of conducting passageways that transport air into and out of the lungs; purifying, humidifying and warming the air as it travels inwards. The organs of the upper respiratory tract are those from the nose to the superior portion of the larynx. The lower respiratory tract consists of the inferior portion of the larynx, trachea, the bronchi and the lungs. The primary role of the lower respiratory tract is gas exchange, which occurs through terminal air sacs, alveoli, located deep within the lungs.