What is phylum Mollusca?
Molluscs have a mantle or mass of soft flesh that covers the soft body and encloses the internal organs. In many species, the mantle produces a hard shell. Not all molluscs produce a shell. Many molluscs have a radula, which, in most species, is a rasp-like scraping organ used in feeding (Fig.
What are characteristics of phylum Mollusca?
Molluscs. The phylum Mollusca is defined by several special characteristics. These defining characteristics include a mantle with a mantle cavity, a shell (except where lost), visceral mass, foot, and radula. The odontophore is in the mouth of most mollusks and it supports the radula (a ribbon of teeth).
How do you identify phylum Mollusca?
Characteristic Features of Phylum Mollusca
- They are bilaterally symmetrical.
- They are triploblastic, which three layers.
- They show organ system grade of organisation.
- The body is soft and unsegmented.
- Body is divisible into three regions – head, a visceral mass, and ventral foot.
- Body is covered by a mantle and shell.
How are mollusks classified?
Living mollusks are usually grouped into eight classes: Gastropoda (see gastropod), Bivalvia or Pelecypoda (see bivalve), Cephalopoda (see cephalopod), Scaphopoda (tusk shells), Aplacophora (Solenogasters), Caudofoveata (sometimes included in the Aplacophora order), Polyplacophora (chitons), and Monoplacophora.
Which of these class is phylum Mollusca?
Classes in Phylum Mollusca This phylum can be segregated into seven classes: Aplacophora, Monoplacophora, Polyplacophora, Bivalvia, Gastropoda, Cephalopoda, and Scaphopoda.
Where are phylum Mollusca found?
marine environment
Molluscs occur in almost every habitat found on Earth, where they are often the most conspicuous organisms. While most are found in the marine environment, extending from the intertidal to the deepest oceans, several major gastropod clades live predominantly in freshwater or terrestrial habitats.
What are the economic values of the phylum Mollusca?
Many gastropods, bivalves, and cephalopods are a source of food for many cultures and therefore play an important role in the fishing industries of many countries. In addition to their economic value as food, mollusks are also used to make jewelry the most notable and valuable example of which is pearl jewelry.
What are the three classes of the Mollusca phylum and what defines each class?
Mollusks are subdivided into seven classes with most species found in three of those classes: Gastropoda, Bivalvia, and Cephalopoda. Gastropods make up the largest class of mollusks, and they include both snails and slugs.
Which of the following belongs to phylum Mollusca?
Mollusca is one of the most diverse groups of animals on the planet, with at least 50,000 living species (and more likely around 200,000). It includes such familiar organisms as snails, octopuses, squid, clams, scallops, oysters, and chitons.
What are the 3 major classes of phylum Mollusca?
The major classes of living mollusks include gastropods, bivalves, and cephalopods (Figure below).
- Gastropods. Gastropods include snails and slugs. They use their foot to crawl.
- Bivalves. Bivalves include clams, scallops, oysters, and mussels.
- Cephalopods. Cephalopods include the octopus and squid.
What are the three most common classes in phylum Mollusca?
The three major groups of mollusks are gastropods, bivalves, and cephalopods (SEF ul o pods). The largest group is the gastropods. These are mollusks like snails and slugs that have just one shell or no shell at all.