Part 3 passes from normal tissue growth to cancer. Older cells are shown at their degenerative stage. Motile cells are active against degenerative ones. Reaction after radium; a clock is present in the top right of the frame to illustrate the pasing of time. 00:06:40 approx an intertitle explains that the scientific part of the film was photographed by the late Dr. R. G. Canti when he was investigating the effect of radium and x-rays on living tissues. The original cinemotographic apparatus he designed is shown.