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THE TUBE WORM
The giant tube worm, also known to science as Raffia pachyptila, were totally Unknown to science until scientists researching the deep Pacific Ocean floor discovered Strange hydrothermal vents on the ocean floor. Powered by volcanic heat, these vents circulate water that seeps down through cracks or faults in the rock. When the water emerges from the vent, it is rich in chemicals and minerals. Scientists were shocked to an entire ecosystem of animals around these vents. These organisms are unique because they do not depend on sunlight for their source of energy. Instead the feed on tiny bacteria that gets their energy directly from the chemicals in the water in a process known as chemosynthesis. The hydrothermal vents have been called "black smokers" because of the dark color of the material they eject. The giant tube worms grow up to eight feet in length and have no mouth or gut. They depend on symbiotic bacteria that live inside them for their food. These bacteria convert the chemicals from the vents into food for the worm. When the worms are very tiny, they have a primitive mouth and gut through which the bacteria enter. As the worm grows older, the mouth and gut dais pear, trapping the bacteria inside. The worm's tube is composed of a tough, natural material called chitin. Entire communities of shrimps and crabs have been found living around these attaints.
OTHER NAME: beard worm
SCIENTIFIC NAME: raffia pachyptila
SIZE RANGE: up to 8 feet long HABITAT: pacific Ocean DEPTH RANGE: over 5000 feet KINGDOM: Animally CLASS: Polychaeta
FAMILY: Siboglinidae
GENUS: Raffia
The tube worm has 6 body parts
1) Plume
This soft, bright-red structure serves the same purpose as a
Mouth would if the tubeworm had one. It sucks in the ingredients that the
Microbes living in the worm's body will use to fashion its food. These
Three ingredients -- oxygen and carbon dioxide in seawater and hydrogen
Sulfide in the superheated water erupting from the vent or black
Smoker -- tend to react violently when they come into contact with Each other. Yet using special hemoglobin’s in its blood-rich plume (Hence the red color), the tubeworm has found a way to transport the Ingredients in its blood without this reaction taking place and without the toxic hydrogen sulfide poisoning it, as it would you or me.
2) Vestment
Though it may not look like much, this part of the worm is like Mission Control. A muscular structure, it helps to anchor the upper portion of the worm in the
Tube. It provides safe passage for the blood heading from the plume to the
Toothsome. It generates new tube material. It holds the reproductive pores from
Which the worm releases sperm or eggs during spawning; these combine in the water
To make baby tubeworms. Finally, along with various glands, this structure
Harbors simplified versions of the two organs that most closely bind this Primitive creature to its fellow animals: the heart and the brain.
3) Toothsome
This organ of dark green-brown spongy tissue is where the real action takes place. Here, the microbes that live symbiotically in the worm make their home in special cells. (Quite a few microbes live here: an estimated 285 billion bacteria per ounce of tissue.) In exchange for a safe, cozy place to live, they give the worm all the food it needs. Those three ingredients pumped down from the plume -- oxygen, carbon
Dioxide, and hydrogen sulfide -- and then controlling their reaction. In Essence, the microbes use the chemical energy released from the oxidation Of sulfide into sulfate to fix carbon dioxide into the organic carbon that Nourishes both the microbes and the worm. It's a good deal for both
Creatures -- until, that is, the tubeworm decides to digest a few microbes
For variety3)
4) Trunk
Imagine having no anus. Waste would have nowhere to go, right? Well, that’s the case with the tubeworm. It has no anus, and so the sulfate left over after the microbes have done their business is simply stored in the animal’s body. Since giant tubeworms can live several decades, you can imagine quite a heap of this stuff building up in their tissues. Yet it is not this waste material but sulfide in the worm's bloodstream that gives the animal its powerful rotten-egg stench. Biologists dissecting tubeworms brought up from the deep say it's one of the nastiest smells you'd ever want to put your nostrils to.
5) Tube
This hard cylinder, which varies in thickness between and even within specie of tubeworm, is basically like the shell of a lobster or crab. (Scientists call it a "chitin proteoglycan/protein complex.") It grows as the worm grows, providing a safe home for the animal. The delicate plume, which is the tubeworm's only exposed part, can be retracted into the tube at a moment’s notice, such as when a hungry fish happens by, hoping to nibble the plume.
6) Opisthosome
Like the vestment, the opisthosome produces new tube material and helps
Anchor the worm in its tube, which is often planted deep within the crevice
Of a black smoker. Giant tubeworms can reach well over a yard long, and the
Temperatures they have to cope with over that length boggle the mind.
Imagine having your head in near-freezing water and your foot planted in
Scalding rock. That's what tubeworms have to deal with: biologists have
Measured temperatures at a worm's plume of 35°F while that at its base is
86°F.
The tube worm can be red
Weird tube worms of the deepest seas
In 1900, a strange tube-dwelling worm was dredged from deep waters around Indonesia. While somewhat resembling tube-dwelling annelids, it lacked obvious segmentation; even More strangely, it also lacked a mouth, gut, or anus. This was the first discovery of the Pogonophora, an animal phylum restricted to the deep sea and remarkably common in certain habitats there. About 80 pogonophoran species are known today, with new species still being discovered. One of the most spectacular zoological discoveries of recent years was the finding in 1977 of giant pogonophoran worms, 1.5 meters long, growing in heated, sulfur-rich water around warm-water vents in the Pacific Ocean, 2600 meters below the surface (pictured at right). These worms are sometimes placed in their own phylum, the Vestimentifera, but they are similar to pogonophorans in most respects, and the current tendency is to group these rift-dwelling worms together with the rest of the Pogonophora into one phylum. The name Pogonophora is Greek for "beard-bearers," and comes from the fact that many species have from one to many tentacles at the anterior end. These tentacles somewhat resemble the lophophore found in animals like brachiopods and bryozoans, as well as the feeding tentacles of certain chordates. The incompletely known anatomy of pogonophorans was interpreted to show that pogonophorans were chordate relatives. Because pogonophorans live with their lower ends buried in mud, and were broken during the dredging process, it was not until 1964 that a complete pogonophoran was recovered. It turned out that pogonophorans have a segmented posterior end of the body -- the opisthosoma -- that bears setae and resembles an annelid body. The forward part of the body, or presume, is unregimented. Because of the segmented opisthosoma, and because pogonophoran larvae have been found to look very much like annelid larvae, pogonophorans are now considered to be close relatives of the annelids, and are classified with them in a larger group, the Trochozoa.
How do pogonophorans feed with no mouth or gut? Some nutrition is provided by absorbing nutrients directly from the water with the tentacles. But most of a pogonophoran's nutrition is provided by symbiotic bacteria living inside the worm, in a specialized organ known as the toothsome that develops from the embryonic gut. Inside the toothsome, these bacteria oxidize sulfur-containing compounds such as hydrogen sulfide, which pogonophorans absorb through their tentacles -- the bright red color of
Rift-dwelling pogonophoran tentacles is due to hemoglobin, which absorbs both sulfides
And oxygen for the use of the bacteria. The bacteria derive energy from sulfur oxidation, Which they use to fix carbon into larger organic molecules, on which the pogonophoran feeds.
The fossil record of pogonophorans may extend back to the Vending Period; long thin tubes known as sabelliditids have been found in rocks of that age and somewhat resemble pogonophoran tubes. However, studies on sabelliditid structure have proved inconclusive in determining exactly what these fossils were. A few fossil pogonophoran-like tubes have turned up in later deposits (e.g. Adipose 1967), but pogonophorans are generally quite rare as fossils.
Resembling giant lipsticks, tubeworms (Raffia pachyptila) live over a mile deep on the Pacific Ocean floor near hydrothermal vents. They may grow to about 3 meters (8 ft) long. The worms’ white tube home is made of a tough, natural material called chitin (pronounced “kite-in”). Tubeworms have no mouth, eyes, or stomach (“gut”). Their survival depends on a symbiotic relationship with the billions of bacteria that live inside of them. These bacteria convert the chemicals that shoot out of the hydrothermal vents into food for the worm. This chemical- based food-making process is referred to as chemosynthesis. Since a tubeworm has no mouth, how do bacteria enter the worm? Scientists have found that, during its earliest stages, the tubeworm does have a mouth and gut for bacteria to enter. But as the worm grows, these features disappear! While the tubeworm depends on the bacteria that live in its body for energy and food, sometimes tubeworms provide food for other deep-sea dwellers. Fish and crabs may nibble off the tubeworm’s red plume.
The deep-sea tube worm Raffia pachyptila Jones possesses a complex of three extra cellular Hobs: two in the vascular compartment, V1 (approximately 3500 kea) and V2 (approximately 400 kea), and one in the colonic cavity, C1 The deep-sea tube worm Riftia pachyptila Jones possesses a complex of three extracellular Hbs: two in the vascular compartment, V1 (approximately 3500 kDa) and V2 (approximately 400 kDa), and one in the coelomic cavity, C1 (approximately 400 kDa). These native Hbs, their dissociation products and derivatives were subjected to electrospray ionization mass spectrometry (ESI-MS). The data were analyzed by the maximum entropy deconvolution system. We identified three groups of peaks for V1 Hb, at approximately 16, 23 27, and 30 kDa, corresponding to (i) two monomeric globin chains, b (Mr 16,133.5) and c (Mr 16,805.9); (ii) four linker subunits, L1 L4 (Mr 23,505.2, 23,851.4, 26,342.4, and 27,425.8, respectively); and (iii) one disulfide-bonded dimer D1 (Mr 31,720.7) composed of globin chains d (Mr 15,578.5) and e (Mr 16, 148.3). V2 and C1 Hbs had no linkers and contained a glycosylated monomeric globin chain, a (Mr 15,933.4) and a second dimer D2 (Mr 32,511.7) composed of chains e and f (Mr 16,368.1). The dimer D1 was absent from C1 Hb, clearly differentiating V2 and C1 Hbs. These Hbs were also subjected to SDS-PAGE analysis for comparative purposes. The following models are proposed ((cD1)(bD1)3) for the one-twelfth protomer of V1 Hb, ((cD)(bD)6(aD)) (D corresponding to either D1 or D2) for V2 and C1 Hbs. HBL V1 Hb would be composed of 180 polypeptide chains with 144 globin chains and 36 linker chains, each twelfth being in contact with three linker subunits, providing a total molecular mass = 3285 kDa. V2 and C1 would be composed of 24 globin chains providing a total molecular mass = 403 kDa and 406 kDa, respectively. These results are in excellent agreement with experimental Mr determined by STEM mass mapping and malls.
TUBE WORM FOSSILS
