Pronunciation: sell-enter-on: (plural)coelentera.
Multitasking for a simple world
The coelenteron is a central sac-like structure in organisms of the phyla
Cnidaria and
Ctenophora, collectively known as
coelenterates. These are relatively simple yet radially symmetrical animals. Examples of animals with a coelenteron are
anemones, comb
jellyfish,
hydras, and
corals.
Though the structure is not properly an organ, it does have tissues which perform specific tasks. It performs digestion, taking in food, digesting it, and excreting waste products.
It also serves a respiratory function, allowing dissolved oxygen in the water to be directly absorbed by cells designed for that purpose, then releases waste gases, completing the cycle.
The coelenteron serves the need for a skeletal structure by using retained water to provide some support to the organism.
The body cavity also serves in some groups as a receptacle for sperm and eggs.
This all purpose structure possesses a single opening which is itself controlled by a sphincter muscle which allows for intake and discharge of water.
Sources:
http://www.britannica.com/eb/topic-124142/coelenteron
http://darwin.nhm.ku.edu/inverts/InterGlossary/listofterms/Coelenteron.htm
http://www.daviddarling.info/encyclopedia/C/coelenteron.html
http://www.encarta.ca/dictionary_1861598353/coelenteron.html
http://www.britannica.com/EBchecked/topic/122750/cnidarian/31891/General-
features#tab=active~checked%2Citems~checked&title=cnidarian%20%3A%3A%
20General%20features%20--%20Britannica%20Online%20Encyclopedia