Everything Totally Explained


Ask & we'll explain, totally!
Calcareous sponge
Totally Explained


  NEW! All the latest news in the worlds of computer gaming, entertainment, the environment,  
finance, health, politics, science, stocks & shares, technology and much, much, more.  


View this entry using RSS

Everything about Calcaerous Sponges totally explained

The calcareous sponges of class Calcarea are members of the animal phylum Porifera, the cellular sponges. They are characterized by spicules made out of calcium carbonate in the form of calcite or aragonite. While most have three points, the spicule of a calcareous sponge may have two to four points.
   All sponges in this class are strictly marine dwellers. All three sponge body plans are represented within class Calcarea : asconoid, syconoid, and leuconoid. Typically, the Calcarea are very small, measuring about 7-10 cm (3-4 inches) in height. Of the 15,000 or so species of Porifera that exist, only 400 of those are Calcareans.
   Species of Calcarea vary from radially symmetrical vase-shaped body types to colonies made up of a reticulum of thin tubes or irregular massive forms. Calcareous sponges are generally sedentary filter feeders, lacking any real tissues. Calcareous sponges are most commonly found in shallow tropical waters. Generally, Calcarea are small sponges. The different shapes of calcareous sponges are relatively simple, either purse, vase, pear or cylinder-shaped. The skeleton has either a mesh or honeycomb structure. Unlike most other sponges, calcareous sponges lack hollow canals, which makes the sponge stronger.
   Calcarean sponges first appeared during the Cambrian and their diversity was greatest during the Cretaceous Period. Recent molecular analysis suggests that the class Calcarea should be delegated as a phylum, in particular the first to have diverged in the Kingdom Animalia; the other sponges belong to the phylum Silicarea.

Further Information

Get more info on 'Calcaerous Sponges'.


External Link Exchanges

Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

    <a href="http://calcareous_sponge.totallyexplained.com">Calcareous sponge Totally Explained</a>

Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
   As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.



Copyright © 2007-8 totallyexplained.com | Licensed under the GNU Free Documentation License | Site Map
This article contains text from the Wikipedia article Calcareous sponge (History) and is released under the GFDL | RSS Version