How do landsnails get their shells?
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Here's a piece of the answer:\n\nThe important thing to remember is that the snails MUST have a constant supply of calcium to keep the shell strong (the shell is, after all, the snail's home, and without it, he'd die!!).
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sand is small pieces of rock that has been eroded away from a larger stone.it would take years to get a few pounds of sand from a 25 pound rock but wind rain and snow will break down the rock to produce sand. soil is dirt formed from leaves and twigs from trees. all this will decay and produce soil along with rain and other dying vegetation.go into a densely wooded area and you will find soil.be sure its a hardwood forest.that means maples oaks and other varieties of trees but not conifers, conifers are of the pine family and fir all evergreens.the foilage dropped this fall will take about 2 1/2 to 3 years to decay enough to be soil which is the best for growing flowers and bulbs
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maybe Water-stones!!!!!
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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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Pearls come from a group of water organisms called pearl molluscs, which includes oysters, mussels, and clams from both freshwater and saltwater. The pearl itself actually begins as an irritant. Sand, a pebble, or a pesky parasitic organism gets inside the oyster's shell. To reduce the irritation, the oyster coats the intruder with layers of a solid, slick material called nacre. \n\nThe oyster's mantle tissue secretes the two main components of nacre: thin layers of the mineral aragoniteand a gluelike substance called conchiolin, which cements the layers together. Because the aragonite is translucent, light interacts with the overlapping layers to give the finished pearl its lustrous appearance. Pearl molluscs also coat the inside of their own shells with nacre, so some shells picked up at a seashore are shiny and iridescent inside.
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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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lil' shrimp things that live in a plastic thing. you put um in there as eggs and they hatch in like a day.
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It is a mollusk that can partly come out of its body. It has mouth and other feeding organs with the help of which it can feed.
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nothing will happen, it will just get soaked. But if you used acid or diluted acid it will become more thin. Acid will eat away the shell.
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probably smashed walnut shells.  its used as a pumice to remove dead skin as it's more abrasive
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They are those little (normally white) hard circle looking things that are growing on the bottom of boats and on whales...just google it...you will find pictures.
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Shells.  All of them can be found alongside a road.
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"All major molluscan groups possess a skeleton, <b>though it has been lost evolutionarily in some members of the phylum</b>. It is probable that the pre-Cambrian ancestor of the mollusks had calcium carbonate spicules embedded in its mantle and outer tissues, as is the case in some modern members."\n\nSo it looks like slugs are gastropods that have lost or abandoned the ability to develop a shell rather than the other way around.
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If you've strolled along a beach in Maine, you've probably found a sand dollar. But what is a sand dollar? Children have been known to say that sand dollars are pressed sand that has been dried or even the money of mermaids washed-up from the deep. In reality, the fragile disk is the skeleton or "test" of a marine animal. By the time the test washes up on the beach it is missing its velvety covering of minute spines and appears somewhat bleached from the sun. It is hard to believe it was once alive. \n\nSand dollars are from the class of marine animals known as Echinoids, spiny skinned creatures. Their relations include the sea lily, the sea cucumber, the star fish and the sea urchin. When alive, the local species, Echinarachnius parma is outfitted in a maroon-colored suit of moveable spines that encompass the entire shell. Like its close relative the sea urchin, the sand dollar has five sets of pores arranged petal pattern. The pores are used to move sea water into its internal water-vascular system which allows for movement. \n\nSand dollars live beyond mean low water on top of or just beneath the surface of sandy or muddy areas. The spines on the somewhat flattened underside of the animal allow it to burrow or to slowly creep through the sand. Fine, hair-like cilia cover the tiny spines. These cilia, in combination with a mucous coating, move food to the mouth opening which is in the center of the star shaped grooves on the underside of the animal. Its food consists of plankters and organic particles that end up in the sandy bottom. \n\nDue to their diminutive edible parts and relatively hard skeleton, few animals bother sand dollars. One animal found to enjoy them on occasion is the thick-lipped, eel-like ocean pout. \n\nOn the ocean bottom, sand dollars are frequently found together. This is due in part to their preference of soft bottom areas as well as convenience for reproduction. The sexes are separate and gametes are released into the water column as in most echinoids. The free-swimming larvae metamorphose through several stages before the test begins to form and they become bottom dwellers. \n\nSince the sand dollar lives in sandy locations, anyone who would like to collect their shells should comb beaches as the tide recedes. The very best time for collecting is after a heavy storm, as many of the shells that have died are dredged up by the increased wave action.\n\nCheryl Page \n\nInformation for this article was taken from: \n\nGosner, Kenneth L., Guide to Identification of Marine and Estuarine Invertebrates; 1971 by John Wiley & Sons, Inc. \nRobbins, Sarah Fraser and Clarice Yentsch, The Sea Is All About Us ; 1973 Harcourt Brace Jovanovich, Inc.
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Evaporation from the sea. Dig shallow pools and with bis leaves collect the moist. You can also get salt this way. Also collect the water from the rain.
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Sand dollars are of the Phylum Echinodermata, class Echinoidea.   They, like the sea urchin, have no arms or legs  but move around by tiny spines on their body.  Sand dollars are usually found lying in a bed buried under a layer of sand.  If a sand dollar is found alive it will appear to have a layer of very fine hair on its body.  These are the spines.   They are a slow moving grazer that feeds on disintegrating organic material found within their sand beds.
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they probably melt and the shell mite shoot off of it