The two phyla Cnidaria and Ctentophora makeup the radiate animals. Most radiates   corroborate tentacles or oral extensible projections around the oral   fetch up that  be armed with cells that may  melt in   falsification mechanism and capture prey. The cells  shew within the tentacles  be structurally and functionally unique to each phylum, such as the cindocytes in Cnidarians and colloblasts in Ctenophores.               Cnidarians capture prey with special stinging cells called cindocytes. These cells  ar found throughout the epidermis but are especially  immense in the tentacles. Cnidocytes contain a cilium or  special cilium  structure with a kinetosome at its base. This structure is  cognize as the cnidocil and it receives a chemical as fountainhead as tactile stimulation.               The nematocyst is the actual stinging element. The undischarged nematocyst is a  little capsule composed of a chitin-like material containing a  coil tubul   ar  fibril that is continuous of the narrow  ratiocination of the capsule.    Fig1  undischarged NEMATOCYST                 When the cnidocyte is stimulated to discharge, the nematocyst membrane becomes permeable to water, and the high  internecine osmotic  ram causes fluid to rush into the capsule. The osmotic  stuff  locomote rapidly,  freeing the operculum and increasing the hydrostatic pressure. The increased pressure everts the  interweave and drives the nematocyst from the cnidocyte. When the nematocyst is discharged, its cnidocyte is absorbed and a new one replaces it.

               In the Hydra,  in that location are    three functional types of nematocysts. First!   , Pentrants, these are comprised of a  supply that is open at the tip and  usually armed with barbs and spines. When they are discharged, they penetrate the prey and inject poison. The open end of the thread /filament may inject protein toxin that produces a sting.                                         FIG2  pink-slipped NEMATOCYST Second, some nematocysts function by entanglement such as the volvents. These cnidocytes have a tube that is closed at the...                                        If you  ask to get a full essay, order it on our website: 
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