This medical illustration series depicts the anatomy and physiology of the respiratory system. The first view shows all elements of the respiratory system, including the nasal cavity, nasopharynx, tongue, oropharynx, epiglottis, glottis, trachea, lung, bronchus and bronchiole. This illustration includes an insert depicting a cross-section through the bronchiole and insert depicting gas exchange in an alveolus. Two inserts demonstrate and explain the physiology of inspiration and expiration.