Slide 6 of 79
Notes:
First they are large and so it is easier to study the biochemical details of the cell cycle. Secondly they have Synchronous divisions cycles so it is easier to see what is happening (once the egg is fertilized it has a cell cycle of 75 minutes and then 11 synchronous cell cycles of around 30 minutes. This means during the last cell cycle there are approximately 2000 cells entering mitosis at the same time making measuring which proteins are active (inactive) much easier). A third reason is these divisions are without growth and so the control system is simpler.
From the study of frog eggs Marc Kirschner and his colleagues discovered that there was something within the cytoplasm that caused the egg to enter mitosis.
