Porocytes are tubular cells which make up the pores of a sponge known as ostia.
[1] Covering the sponge is a layer of cells known as the pinacoderm, which is composed of pinacocytes.
Myocytes are small muscular cells that open and close the porocytes.
They are present in the Leucosolenia (an asconoid sponge) in the body wall through which water enters the body or they are present in Scypha (a syconoid sponge) as a connection between incurrent canal and radial canal.
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