Freshwater mollusk

Zhang. S. M. and Loker, E. S., Representation of an immune responsive gene family encoding fibrinogen-related proteins in the freshwater mollusk Biomphalaria glabrata, Gene, 341, 255, 2004. 

Goudreau, S.E. Neves, R.J. Sheehan, R. 1993, Effects of wastewater treatment plant effluents of freshwater mollusks in the upper Clinch River, Virginia, USA. Hydrobiologia 252 211—230. 

Van der Oost, R., H. Heida, and A. Opperhuizen. 1988. Polychlorinated biphenyl congeners in sediments, plankton, mollusks, crustaceans, and eel in a freshwater lake implications of using reference chemicals and indicator organisms in bioaccumulation studies. Arch. Environ. Contam. Toxicol. 17 721-729. 

Fracture Fracture describes the way a substance breaks when it neither cleaves nor parts (breaks along plane of weakness). The most common kind of visible fracture is conchoidal, which produces curved, smooth surfaces (glass, quartz). Freshwater pearl one that occurs in a freshwater (non-marine) mollusk. Gem a general term used to describe precious and semi-precious stones, usually after they have been cut and polished. In archaeology, it refers only to engraved stones (cameo, intaglio, seals, etc.). 

A variety of invertebrates are also used in these series of tests. Freshwater invertebrates are often represented by daphnids, insect larvae, crayfish, and mollusks. Various mysid, shrimp, and crab species are used to represent marine invertebrates. 

Shellfish belong to the biological group of species known as mollusks, animals with a shell and a foot. Univalve mollusks have one shell and include many species of snails, conchs, and others. Bivalve mollusks have two shells and include clams, scallops, and oysters. There are many species of mollusks and both freshwater and salt water varieties. In addition to their use as food, shells were often used to make beads, fishhooks and other objects. Crushed shells have been used as a source of lime, for pottery temper, and as construction material. In some areas such as the South Pacific, shells of species like the cowrie have been traded as valued items over long distances and even used as money. 

Fig. 1 The oxygen isotopic composition of carbonate mollusk shells from the Aral Sea [15]. (1) clayey mud (2) clayey-silty mud (3) sand (4) marine shell debris (5) freshwater shell debris (6) peat (7) plant debris (8) gypsum (9-10) boundaries [(9) gradual (10) sharp)] (11-12) stages [(11) transgressive (12) regressive)]...

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