What is "choanocyte"

choanocyte \cho"a*no*cyte`\ (k[=o]"[.a]*n[-o]*s[imac]t`; k[=o]*[a^]n"[-o]*s[imac]t`), n. [Gr. choa`nh funnel + -cyte.] any of the flagellated cells in sponges having a collar of cytoplasm around base of the flagellum; they maintain a flow of water through the body.

Syn: collar cell.

n. any of the cells in sponges that contain a flagellum, and are used to control the movement of water

n. any of the flagellated cells in sponges having a collar of cytoplasm around the flagellum; they maintain a flow of water through the body [syn: collar cell]

Choanocytes (also known as "collar cells") are cells that line the interior of asconoid, syconoid and leuconoid body type sponges that contain a central flagellum, or undulipodia, surrounded by a collar of microvilli which are connected by a thin membrane. They make up Choanoderm, a type of cell layer found in sponges. The cell has the closest resemblance to the choanoflagellates which are the closest related single celled protists to the animal kingdom (metazoans). The flagellae beat regularly, creating a water flow across the microvilli which can then filter nutrients from the water taken from the collar of the sponge. Food particles are then phagocytosed by the cell.