of, for example, 12 mesenteries may be complete, while secondary and tertiary cycles of mesenteries positioned between them may be complete or incomplete. In the pharyngeal region complete mesenteries have holes in them that allow water to pass through. Below the pharynx the mesenteries have a free (unattached) margin that recurves toward the column wall. This unattached margin has three lobes and is called a mesenterial filament. It is important in digestion of food. The side lobes on the mesenterial filament have ciliated cells wrhich aid in water circulation within the coelenteron. The middle lobe is armed with nemato-cysts and lined with enzyme-secreting gland cells. At the base of the mesenterial filament the middle lobe may continue as a thread-like structure called an acontium. This structure serves digestive function and also a defensive role as anemones with acontia may eject the filaments through the body wa 11 in response to a disturbance. The filaments can sting and partially digest the tissue of an attacking organism. Anemones without acontia (as well as corallimorpharia and stony corals) may also eject whitish stringy mesenterial filaments through the mouth or body wall for defense or agression.
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The word aquarium originates from the ancient Latin language, aqua meaning water and the suffix rium meaning place or building. Aquariums are beautiful and look good anywhere! Home aquariums are becoming more and more popular, it is a hobby that many people are flocking too and fish shops are on the rise. Fish are generally easy to keep although do they need quite a bit of attention. Puppies and kittens were the typical pet but now fish are becoming more and more frequent in house holds. In recent years fish shops have noticed a great increase in the rise of people wanting to purchase aquariums and fish, the boom has been great for local shops as the fish industry hasnt been such a great industry before now.