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The idea of a tooth worm is a theory of the cause of dental caries, periodontitis and toothaches. Once widespread, the belief is now obsolete, having been superseded by more scientific rationales. It was supposed that the disease was caused by small worms resident within the tooth, eating it away. [1]
The cilia allow the worms to glide along in the water between sand grains, although they also use muscles, allowing the body to twist or contract, for movement. They have no body cavity, and no circulatory or respiratory system. The nervous system is simple, and restricted to the outer layers of the body wall.
It is known that they feed more frequently with higher temperatures. Planktonic chaetognaths often must swim continuously, with a "hop and sink" behaviour, to keep themselves in the desired location in the water layer, and swim actively to catch prey. They all tend to keep the body slightly slanted with the head pointing downwards. [3]
Gongylonema pulchrum was first named and presented with its own species by Molin in 1857. The first reported case was in 1850 by Dr. Joseph Leidy, when he identified a worm "obtained from the mouth of a child" from the Philadelphia Academy (however, an earlier case may have been treated in patient Elizabeth Livingstone in the seventeenth century [2]).
The ctinidia lie mainly within the branchial siphon, through which the animal pumps the water that passes over the gills. The two siphons are very long and protrude from the posterior end of the animal. Where they leave the end of the main part of the body, the siphons pass between a pair of calcareous plates called pallets.
The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The Annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion.
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The worms are neutrally buoyant, and have been observed floating along with their mouth parts facing downward, and their hind parts towards the ocean surface. As these worms have shown no ability to swim or otherwise propel themselves through the water, and have no long, protruding appendages to catch prey with, they must rely on filter feeding ...