They play a role in movement (contracting and stretching), cell adhesion, signaling, phagocytosis, and polarity.
[2] Pinacocytes are filled with mesohyl which is a gel like substance that helps maintain the shape and structure of the sponge.
[3] These are the cells in contact with the sponge's substrate (the surface to which it is attached).
Exopinococytes produce spicules which is a needle like process that serves as structure for the organism.
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