Segment 1 Micro photographs are used to show the first stages of the gestation of the ovum. The process of segmentation is demonstrated on the ovum of an axolotl. The fertilised ovum is divided into two daughter cells. There is some time lapse footage of two cells forming. A further division produces four cells - there is time lapse footage of four cells forming, then eight cells forming, then multiple cells forming into large bunch of cells. By continued division a solid cluster of cells is formed, called the morula. Each cell division is preceded by a corresponding division of the nuclei. In the interior of the morula the germinal vesicle is formed. (This cannot be seen in the picture) There is a time lapse shot of the morula and continued cell division. At a certain point on the outer surface a narrow canal is created by invagination of the germinal vesicle (gastrolation). Time lapse footage shows slight chances on the surface of the blastocyst. Time start:00:00:00:00 Time end:00:05:10:02 Length:00:05:10:02
Segment 2 Micro photographs are used to show further stages of gestation of the ovum. Whilst in the interior a mesoderm is undergoing differentiation and the medullary plate is forming on the surface. At the caudal end of the medullary plate (left half in pictures) the primitive orifice is visible. The two folds of the medullary place grow over to meet each other and finally coalesce, thus forming the medullary tube. There is a time lapse shot of this development. Further differentiation in the embryo takes place during a rotary movement which is shown greatly accelerated on the film. Time lapse shows accelerated rotation of the ovum (seen spinning). Time start:00:05:10:02 Time end:00:08:53:07 Length:00:03:43:04