Description: Segment 1 An illustration of the human body is shown, with the captions 'The diaphragm moves up and down' and 'The ribs move outward and upward'. A model made from rubber tubes and a glass jar shows how the diaphragm helps to enlarge the chest cavity and draw air into the lungs. Then a demonstration of artificial respiration is performed by two men. An illustration shows the air passages, with captions pointing out the nostrils and sinuses. An illustration of the skull shows the turbinate bones and the sinuses. Another drawing shows that the breathing tubes are lined with ciliated epithelium, which are then shown in close-up. The make-up of the nose and throat area is then explained, with captions pointing out the adenoids, tonsil, pharynx, larynx, trachea, esophagus and epiglottis. A large model of the throat is displayed. Time start: 00:00:00:00 Time end: 00:05:30:08 Length: 00:05:30:08 Segment 2 An animation shows how the vocal cords change in position to produce a change in the pitch of the voice. Illustrations show the structure and function of the lungs from different angles, and an animation shows the inflation of the lungs during ordinary breathing and during vigorous exercise. A man is shown breathing into an apparatus that inflates as he breathes. Parts of the lung are shown, including the trachea, bronchi and bronchial tubes, and then close up drawings of the branching tip of a bronchial tube and alveoli. An illustration of the wall between two alveoli also shows the epithelial cells, the capillary wall, air space on each side of the wall, red blood corpuscles, and an animation then shows the blood giving off carbon dioxide and taking up oxygen. The film ends with shots of men rowing and swimming. Time start:00:05:30:08 Time end:00:11:10:11 Length: 00:05:30:03