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