The differentiating capacity of dissociated sponge cells.

1. The intricacy of regeneration depends largely on the behaviour of cells during early hours of contact. 2. Cellular contact is a necessary prerequisite to bring about the phenomenon of regeneration. 3. Cells dedifferentiate and attain a generalized state before regeneration. 4. Certain unipotent cells can only redifferentiate into original fate e.g., pinacocytes, scleroblasts, choanocytes. 5. Other types of cells completely lose their original characteristics and become totipotent i.e. redifferentiate into other types of cells. These are called pluripotent cells e.g. amoeboid cells. 6. Definite orientation of cells are observed from the beginning of cell aggregation. Archeocytes remain in the periphery and other cells in the middle of the mass. 7. Redifferentiation begins from 4-6 hours stage of reaggregation.