what are coral skeletons made up of?
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Calcium Carbonate .. \n\nCheck this web site its nice ... \n\nhttp://www.mbmp.org/corals.htm
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sand comes from shells and coral,finely broken over time. And from fish ingesting coral and excreting it as sand.
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Pearls are formed inside the shell of certain bivalve mollusks. As a response to an irritating object inside its shell, the mollusk will deposit layers of calcium carbonate (CaCO3) in the form of the minerals aragonite or calcite (both crystalline forms of calcium carbonate) held together by an organic horn-like compound called conchiolin. This combination of calcium carbonate and conchiolin is called nacre, or as most know it, mother-of-pearl.
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Here is the boring wikipedia answer, there is another specific answer for California beach sand at the end:\n\nSand is an example of a class of materials called granular matter. Sand is a naturally occurring, finely divided rock, comprising particles or granules ranging in size from 0.0625 (or 1/16) to 2 millimeters. An individual particle in this range size is termed a sand grain. The next smaller size class in geology is silt: particles below 0.0625 mm down to 0.004 mm in size. The next larger size class above sand is gravel, with particles ranging from 2 mm up to 64 mm (see grain size for standards in use). Sand feels gritty when rubbed between your fingers (silt feels like flour).\n\n\nThe most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide), usually in the form of quartz which because of its chemical inertness and considerable hardness is quite resistant to weathering. However, the composition of sand varies according to local rock sources and conditions. The bright white sands found in tropical and subtropical coastal settings are ground-up limestone. Arkose is a sand or sandstone with considerable feldspar content which is derived from the weathering and erosion of a usually nearby granite. Some locations have sands that contain magnetite, chlorite, glauconite, or gypsum. Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts. The chlorite-glauconite bearing sands are typically green in color, as are sands derived from basalts (lavas) with a high olivine content. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, white color. Sand deposits in some areas contain garnets and other resistant minerals, including some small gemstones.\n\nHere's another specific answer for California:\n\nBeaches vary in color according to the mineral content of the sand, which is also a clue to the origin to the eroded sediments that make up the sand supply. eroded shale cliffs create the charcoal gray beach sand at Shelter Cove in Humboldt County. North of Humboldt Bay, the coarse sands of Agate Beach are multicolored agates that have been ground and polished by the surf. Ground quartz and feldspar mineral make up the white beaches of Carmel, while a few miles to the north in Sand City, amber colored sand indicates the presence of iron mineral. Close inspection reveals that white sand beaches are mosaic of pale quartz grains, pink green or white feldspar and fleck o black mica.
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Sharks do have backbones, as all vertebrates. Sharks do not have true bone, but their cartilaginous skeleton can be heavily calcified so that their vertebrae have the apperance of "bone" because they look like hard white cylindric spools. You might have seen their vertebrae made into necklaces and such by artisans. \nThis is what a shark trunk vertebra looks like:\nhttp://www.marinebiodiversity.ca/shark/english/porbeagle_vertebra__copy.jpg\nAnd without the neural and haemal arches they look like this: \nhttp://homepage.mac.com/mollet/Cm/BaskingSharkImages/basking%20shark%20vertebra%204.jpg\n\nAnd these are fragments of backbones:\nhttp://www.indonetwork.info/member/77806_backbone2.jpg\n\n(Notice the white color because the cartilage is calcified.)\n\nAlmost all the cartilaginous fish have backbones made of vertebrae (i.e. both sharks and skates/rays); the exception are the chimaeras or ratfish which do not have vertebrae, but retain a notochord (the primitive condition).
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Cnidarians live mainly in marine environments. Examples of cnidarians are the jellyfish, sea anemones, and corals. They are different from sponges because sponges have assymmetry which means they have no definite shape. Cnidarians have radial symmetry.
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rocks are made up of minerals
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Hermatypic corals (the ones that form coral reefs) have symbiotic zooxanthellae (unicellular algae) within their tissues; the algae receive protection and housing from the polyps, and enable them to produce their calcareous exoskeleton.\nThere are sea anemones that attach to the dorsum of crabs, marine snails, etc. Thus the anemone "travels free" and the other animal is protected. \nMany species of small fishes and crustaceans shelter beneath the umbella of some jellyfish (read example at the link).
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To summarize the above the answer, no they are not made of fossilized wood.
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The skeleton of an adult human is comprised of 206 bones. \n\nThe skeleton of an infant contains 350 (bones fuse together as you grow up)\n\nThis completely answers your question
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To the above mention person, idiot this is english if you are not versed in scientific terms don't go spouting nonsense. Cartilages are not true bone material, they are soft tissue like what our noses and most non skeletal fishes such as sharks and rays are composed of. But a toad has a skeletal structure and the cartilages are the same as a humans, found at the bridge of the nose area.
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bones are made of calcium and vinegar (an acid) can erode bones.
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They are made up of a complex double salt:CALCIUM SULPHATE.CALCIUM SILICATE          \nformula:CaSO4.CaSiO2.\nThe teeth is covered by an enamel of a highly inert and non reactive coating that does not react with most of metals and non-metals. But it can be deatched by excessive rubbing of teeth b either brushing or chewing.
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.... i not sure , they grow in layers though, calcium i think .?? i do know this , they are not skeletons of dead creatures... cretin
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Particulates from 'smoke'.\nSoil that has been eroded by the wind.\nSalt crystals lifted off the sea.\nPollen\nSeeds from plants such as dandelionor orchids.\nWindborne microbes or their spores.\nAnimals, mainly birds and insects, but also spiders and other animals that are blown from place to place.\n\n\n________\n\n>>>> none they are all gases\n\nYeah, like all the material in the ocean is a liquid, right? And all the material in the ground is a solid?\n\nDid you even stop to think before answering?
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Without a skeleton we'd be like a jellyfish on land. Which would make it hard to type into Yahoo Answers.
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Bone is a relatively hard and lightweight composite material, formed mostly of calcium phosphate in the chemical arrangement termed calcium hydroxyapatite. It has relatively high compressive strength but poor tensile strength. While bone is essentially brittle, it does have a degree of significant elasticity contributed by its organic components (chiefly collagen). Bone has an internal mesh-like structure, the density of which may vary at different points.