Glossary
Terminology Description
Terminology Description
Archaeocytes (amoebocytes) Cells with pseudopods, located in the mesohyl. They are used in processing food, distributing it to other cells, and for other functions.
Benthic living at or near the bottom of the seas.
Choanocyte also called collar cells, choanocytes line the inner cavity of the sponge. They have a sticky, funnel shaped collar (that collects food particles) and a flagellum (which whips around, moving water). The sponge obtains its nutrients and oxygen by processing flowing water using choanocytes. Choanocytes are also involved in sponge reproduction; they catch floating sperm.
Epidermis (pinacocyte) the epidermis is the layer of cells that covers the outer surface of the sponge. The thin, flattened cells of the epidermis are called pinacocytes.
Flagellum the whip like structure of a choanocyte; the flagellum moves, pushing water (which contains nourishment) through the sponge
Hermaphrodite an animal in which each adult can act as either the female or the male in reproduction.
Holdfast root like tendrils that attach the sponge to rocks.
Invertebrate an animal without a backbone.
Mesohyl (mesenchyme) the gelatinous layer between the outer body of the sponge and the spongocoel (the inner cavity).
Osculum a large opening in a sponge through which water flows out of the sponge. Sponges may have more than one oscula.
Ostia a series of tiny pores all over the body of a sponge that let water into the sponge. One of these is called an ostium.
Pinacocyte pinacocytes are the thin, flattened cells of the epidermis, the sponge's outer layer of cells.
Porocyte cells with pores that allow water into the sponge; they are located all over the sponge's body.
Sessile permanently attached to a substrate and unable to move on its own. Adult sponges are sessile.
Spicule spicules are sharp spikes (made of calcium carbonate) located in the mesohyl. Spicules form the "skeleton" of many sponges.
Spongin the flexible, fibrous fibers that form the skeleton of horny sponges; spongin is located within the mesohyl.
Spongocoel the central, open cavity in a sponge through which water flows.
Water flows into the sponge water flows into a sponge through cells with pores (these cells are called porocytes) located all over its body.
Water flows out of the sponge water flows out of a sponge through large openings called oscula (plural). Each of these large openings is called an osculum.