The majority of bivalves consist of two identical shells that are held together by a flexible hinge. Mussels, a type of bivalve. Example: marine mussel and oyster Bivalvia (/ b aɪ ˈ v æ l v i ə /), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. Class Cephalopoda Which is the largest Mollusc Class? Examples of bivalves are clams, scallops, mussels, and oysters. halves. There are about 80,000 living species are known in this phylum.They usually have the shell and a characteristics ventral muscular foot.In Latin, molluscs are the name of the soft nut with a thin shell, referring to the bivalve shell and the soft-bodied animal within the shell. There are both freshwater and marine bivalve species. The two shells are joined at the dorsal end by a region called the ligament. These bivalves use the hinges to take in food, and are also able to jet some distance away by If you were to separate their two halves (or your two hands), each side perfectly mirrors the other, even though the shell shape itself might not be symmetrical. The oldest part of the shell, the umbo, can be recognized as a large hump on the anterior end of the dorsal side of each shell. A bivalve is characterized by possessing two shells secreted by a mantle that extends in a sheet on either side of the body. The valves are connected to one another at a hinge. A membrane that lines the insides of both shells of a bivalve and protects the internal organs Mollusks Soft, bilaterally symmetrical animals with head (and brain), foot region, coelom, coiled visceral mass, and usually an external or internal shell Respiration: The process of respiration is carried out by plate-like gills. Bivalves are … There are more than 15,000 species of bivalves that live in both marine and freshwater. A valve is half the shell of a mollusk with a two-part shell. Bivalve, (class Bivalvia), any of more than 15,000 species of clams, oysters, mussels, scallops, and other members of the phylum Mollusca characterized by a shell that is divided from front to back into left and right valves. Habitat: Bivalves are aquatic animals. Example: garden snail and slug (shell lost). The two valves are joined by a hinge. Bivalves have a plane of symmetry that cuts between their two valves. The hinge is head together by a ligament and one or two adductor muscles. The term mollusca are the most abduent of all animals. ... What are the shells of these animals used for? Class: Bivalve. They have symmetry similar to our hands. Some common bivalve species include clams, oysters, and mussels. The animal's body is held protectively inside these two shells. digging and anchoring to surfaces. Echinoderms are the animals which have radial symmetry and an endoskeleton made out of calcareous plate. Which mollusc class includes all marine animals? These animals live only in marine environment.These animals lack circulatory and excretory systems. Each side of the shell is a valve; hence gastropods, such as snails, are sometimes called univalves. Most live in sand or mud, and use their foot for. The apex is the tip or point of the shell. These mollusks are called bivalves, and include clams, oysters, and mussels. example- octopus, squids. f. Dorsal border. Mollusks are the animals which consist mentle, foot and and sometimes a shell. These are marine animals with a hinged shell divided into two. The dorsal border is the edge of a bivalve's shell where the hinge is located. Describe their shell 2 lateral valves connected with a hinge Class Bivalvia~ Where do these animals live? Symmetry: These animals are bilaterally symmetrical. g. Apex. A bivalve is a type of aquatic mollusk with a two-sided, symmetrical shell. 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