Uptake of Dissolved Inorganic and Organic Matter

We just mentioned that the host anemone may eat the clown-fishes' solid waste. The clownfish also provide an on-site source of dissolved inorganic nitrogen (via ammonium excreted from the gills), and this benefits the symbiotic zooxanthellae. Of course the vast quantity of water passing over an anemone carries with it small quantities of dissolved inorganic nutrients, so with proper water flow an anemone has all the food it needs brought right to it. Anemones capture organic matter as well and transport it via cillia on the oral disc to the mouth. It is possible that the mucus on the surface of the tentacles, oral disc, and column may serve a function like that known for soft corals of the genus Xenia. The mucus in Xenia is described as a "molecular net" because of its ability to trap organic compounds from the water. It is tempting, then, to equate the pumping behaviour of Xenia polyps to the curious "vibrating" of tentacles in Stichodactyla gigantea and S. baddoni. This behavior certainly serves a light flashing function, but it may also be involved in the capture of dissolved organic compounds under conditions of low water velocity.

Absorption of DOM by sea anemones was first suggested by Putter (1911), and the topic has been further examined by

Schlichter (1980 ' and Schlichter et al. (1987). The large surface of sea anemones is amplified at least tenfold by microvilli on ectodemal cells (Schlichter, 1980). These finger like projections on the cells are characteristic of absorptive epithelia. Strong water flow therefore is important not only for providing the exchange of repiratory gases, but also for supplying dissolved organic food. The anemones are feeding all the time, even though we typically think of feeding in the sense of food caught by the tentacles and passed to the mouth. Dissolved organic material is a major supplemental food source during periods when no solid food is taken (Shick, 1975), and it may be especially important for burrowing anemones which are exposed to high concentrations of DOM, or for small anemones with proportionally high tentacle surface areas (Robbins and Shick, 1980). The capture of DOM including free amino acids on the surface of the anemone is thought to benefit the ectodermal tissues in particular, which are partially isolated from nutritive endodermal tissues by the mesoglea in between that presents a barrier to free diffusion of glucose and amino acids (Shick, 1991; Schlichter, 1973; Chapman and Pardy, 1972; Bradfield and Chapman, 1983).

The COMPLETE guide to Aquariums

The COMPLETE guide to Aquariums

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.

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