... Squid. Giant clam. Some examples of bivalves are oysters, clams, mussels, and scallops. Chiton. A member of the class polyplacophora (Mollusks with many shells) (6) Ammonite. Mollusks that have 2 hinged shells belong to which class. Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion. Current and excurrent siphons circulate water containing food and oxygen through the bivalve. Most mollusks have tentacles for feeding and sensing, and many have a muscular foot. 0. There is a layer of tissue called the mantle between the shell and the body. Members of class Monoplacophora (“bearing one plate”) have a single, cap-like shell enclosing the body. Bivalves have two shells that are hinged on one side, allowing them to open and close. bi = two. They have two hinged shells that close around the animal for protection. Monoplacophorans are deep-sea mollusks equipped with cap-like shells. Tusk shells, also known as scaphopods, have long, cylindrical shells with tentacles extending from one end, which these mollusks use to rope in prey from the surrounding water. valvia = shell : These mollusks have two shells hinged together by a ligament. A mollusk with two shells. gastropods. A cephalopod with 8 arms. CLASS BIVALVIA. 87% average accuracy. 900 seconds . Class Bivalvia • This class includes: clams, mussels, scallops, oysters, cockles, and jingle shells. The majority of mollusks live in the ocean. ... (seashells) includes clams oysters and scallops. cephalopods. 10 times. Mollusks have been evolving in the sea for over 600 million years and there are more than 100,000 mollusks species. An extinct cephalopod with an extensive fossil record. • The only class of molluscs that has two shells. 8 months ago. The two, 'bi', shells are also called valves, which is how these mollusks got their name. Edit. Mollusca QUIZ DRAFT. bivales. Mollusks are members of the phylum mollusca. answer choices . 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. arthropods. Strong adductor muscles open and close the shells. • Most bivalves are filter feeders taking all floating particles out of the water column. Cephalopoda. andielj7508. Gills extract oxygen from the water. This class of mollusks is considered to be the most intelligent. 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. a large bivalve that can weigh over 200kg. Save. Mollusks with two shells are known to the world as bivalves. Tags: Question 5 . Invertebrate. The valves are connected to one another at a hinge. They were long believed to be extinct, but in 1952, zoologists discovered a handful of living species. 9th grade. • The smallest bivalves are microscopic and the largest are 4 feet across. Mollusks have a hard outer shell. The monoplacophorans were believed extinct and only known as fossils until the discovery of Neopilina galatheae in 1952. We can look at two subcategories to find examples of mollusks with shells. SURVEY . Today, scientists have identified nearly two dozen living species. Science. Bivalvia have two identical shells that are hinged together. An animal with no backbone. ... ( seashells ) includes clams oysters and scallops shell: These mollusks their. Shells that are hinged on one side, allowing them to open and close of bivalves microscopic. Cockles, and scallops in 1952, zoologists discovered a handful of living species class Monoplacophora “... 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