With every breath you take, the process of respiration is supplying cells in the body with oxygen they need to carry out important processes. This engaging program highlights the major structures and functions of the respiratory system. Concepts and terminology include: nasal passage, pharynx, larynx, lungs, diaphragm, trachea, bronchial tubes, alveoli, gas exchange, pulmonary circulation, inhalation, exhalation, hemoglobin, asthma, bronchitis, smoking, lung cancer, and pneumonia. .