Possible role of cortical endoplasmic reticulum during the early stages of development.

Ultrastructural evidence shows that, during the early stages of development in D.pictus (up to 90 min after insemination), clusters of smooth endoplasmic reticulum cisternae are involved in the massive formation of cisternae and vescicles. It is suggested that these elements contribute to the turnover of the egg surface and to the formation of the second polar body and Golgi complexes.