pinacocyte

biology

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July 1, 2026

Quick Summary

Pinacocytes are flat cells that form the outer layer, or pinacoderm, of a sponge's body and also line its internal canals. These cells are crucial for the sponge's structure and function.12

Key facts about pinacocytes:
* They form a protective outer covering and line the water-current system's canals.12
* Different types of pinacocytes exist, including those in contact with the attachment surface (basipinacocytes), those on the sponge's exterior (exopinacocytes), and those lining the canals (endopinacocytes).1
* Pinacocytes contain granules and can contract, potentially reducing the sponge's volume when disturbed.1
* In some sponges, specialized cells called porocytes, which contain pores for water entry, are also found on the outer surface and can contract to close these pores.1
* The term "pinacocytal" refers to anything related to pinacocytes.3

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sponge
Water-current system
…found among the cells (pinacocytes), which line the outer surface of the sponge. After passing through a system of incurrent canals and cavities, also lined with pinacocytes, the water reaches the flagellated chambers, enters them through openings (prosopyles), and leaves through other openings (apopyles). The water is expelled through…
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…found among the cells (pinacocytes), which line the outer surface of the sponge. After passing through a system of incurrent canals and cavities, also lined with pinacocytes, the water reaches the flagellated chambers, enters them through openings (prosopyles), and leaves through other openings (apopyles). The water is expelled through…
Read More