Sponges

Poriferans argon commonly referred to as rinses. An early branching military issue in the history of animals separated the sponges from other metazoans. As wholeness would expect based on their phylogenetic position, fossil sponges are among the oldest known animal fossils, dating from the Late Precambrian. Since then, sponges have been indiscreet members of many fossil communities; the number of described fossil genera exceeds 900. The nearly 5,000 living sponge species are classified in the phylum Porifera, which is calm of three distinct groups, the Hexactinellida (glass sponges), the Demospongia, and the Calcarea (calcareous sponges).

Sponges are characterized by the possession of a feed system unique among animals. Poriferans dont have mouths; instead, they have bantam pores in their outer walls through which water system is drawn. Cells in the sponge walls filter goodies from the water as the water is pumped through the body and out other larger openings. The flow of water through the sponge is unidirectional, driven by the beating of flagella which plication the surface of chambers connected by a series of canals.



Sponge cells perform a variety of bodily functions and be to be more independent of each other than are the cells of other animals.

There is an exception to the general description of sponge feeding that you just read above. Read more in the liveliness History & Ecology section to learn virtually the weird and interesting carnivorous sponges.

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