What are the major characteristics of the mollusks?
Main characteristics of Mollusca : Unsegmented soft body with bilateral symmetry. Presence of an internal or external shell. A toothed tongue (made mostly of chitin) called the radula. A mantle which is a fold in the body wall that lines the shell.
Is Mollusca a bilateral symmetry?
The generalized mollusc is bilaterally symmetrical and has a single, “limpet-like” shell on top. The shell is secreted by a mantle covering the upper surface. The underside consists of a single muscular “foot”.
Are molluscs Heterotrophs?
Mollusks are mainly aquatic invertebrates in Phylum Mollusca. They include snails, squids, and clams. Mollusks are either free-living heterotrophs or parasites.
How do you characterize the mollusks?
Mollusks have a hard outer shell. There is a layer of tissue called the mantle between the shell and the body. Most mollusks have tentacles for feeding and sensing, and many have a muscular foot. Mollusks also have a coelom, a complete digestive system, and specialized organs for excretion.
What is the common characteristic of mollusks and crustaceans *?
Crustaceans are aquatic animals that have jointed legs, a hard shell and no backbone, such as crab, crayfish, lobster, prawns and shrimp. Most molluscs have a hinged two-part shell and include clams, mussels, oysters and scallops, as well as various types of octopus, snail and squid.
What are the characteristics of mollusks and crustaceans?
Are mollusks radial or bilateral?
Mollusks are generally considered a phylum of bilaterally symmetrical animals, although there are also many asymmetrical species. Bilateral symmetry means that an organism can only be divided into two equal halves if it is cut from top to bottom along the middle of the anterior-posterior (front-back) axis.
What type of symmetry do mollusks have?
bilateral symmetry
Mollusks have bilateral symmetry. – The two halves of the body mirror each other. Gastropods (snails) ~ eat with a radula (tiny tongue covered with teeth. Cephalopods (squid) ~use tentacles to grab their prey and put it in their powerful jaws.
Are mollusks autotrophic or heterotrophic?
Yes, all mollusks are heterotrophic, because mollusks are animals, and all animals are heterotopic, meaning that they need to consume organic carbon…
What characteristics help mollusks to survive?
Muscular foot used for locomotion and other tasks. A sheath of tissue called a mantle that covers the body and can secrete the shell (if there is one) A mantle cavity that houses the gills or lungs.
What are the main characteristics of a Mollusca?
Molluscs. Main characteristics of Mollusca : A ll modern mollusks have the same fundamental body plan. There are three distinct body zones: a head-foot, a visceral mass and a mantle. Some common features are : Unsegmented soft body with bilateral symmetry Presence of an internal or external shell A toothed tongue (made mostly of chitin)…
Which is part of the mantle does a mollusk have?
Mollusks are eucoelomates, but the coelomic cavity is restricted to a cavity around the heart in adult animals. The mantle cavity, formed inside the mantle, develops independently of the coelomic cavity. It is a multi-purpose space, housing the gills, the anus, organs for sensing food particles in the water, and an outlet for gametes.
How many species of mollusks are there in the world?
There are more than 110,000 species that have been identified. A theoretical, idealized mollusk would crawl on a single flat, muscular foot, and the body would have at least a suggestion of a head at one end and an anus at the other.
Why are mollusks important to the human diet?
Mollusks, because of their ease of capture, edibility and beauty have long been important to mankind. Molluscs of many sorts are eaten by humans: Abilone, Clams, Cockles, Muscles, Octopus, Oysters, Periwinkles, Scallops, Snails, Squid, Whelks, Winkles and many more are all molluscs and all make their contribution to the human diet.