What is colenterata?

Answer 1

That group of thehttp://www.answers.com/topic/radiata whose members typically bear tentacles and possess http://www.answers.com/topic/intrinsic nematocysts. The name http://www.answers.com/topic/cnidaria-invertebrate-zoology is also used for this http://www.answers.com/topic/phylum and is preferred by some because the name Coelenterata, as first used, included the http://www.answers.com/topic/sponge (Porifera) and the http://www.answers.com/topic/comb jellies (Ctenophora), as well as the animals called coelenterates. See alsohttp://www.answers.com/topic/ctenophora-1; http://www.answers.com/topic/porifera-1.

The coelenterates are mainly marine organisms and are best known as http://www.answers.com/topic/jellyfish or medusae, sea anemones, corals, the Portuguese man-of-war, small polypoid forms called hydroids, and the fresh-water hydras. Taken together, the phylum is divisible into three classes as follows: (1) Hydrozoa, the hydroids, hydras, and hydrozoan or craspedote jellyfish (hydromedusae); (2) Scyphozoa, the http://www.answers.com/topic/acraspedote jellyfish; and (3) Anthozoa, the sea anemones, corals, sea fans, sea pens, and sea pansies. See also http://www.answers.com/topic/anthozoa-1; http://www.answers.com/topic/hydrozoa-1; http://www.answers.com/topic/scyphozoa-1.

It is convenient to recognize two basic body forms in this phylum, the http://www.answers.com/topic/polyp and the http://www.answers.com/topic/medusa, into which all coelenterates can be classified. The polyp and the medusa, however, have many features in common (see illustration).