GENERAL HISTOLOGY

Detailed explanation-1: -mollusk, also spelled mollusc, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body.

Detailed explanation-2: -Gastropods are the most diverse group of molluscs (Fig. 3.59). The ones we usually think of are snails and slugs. Most gastropods have a calcareous shell protecting the soft-bodied animal inside.

Detailed explanation-3: -Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (/ˈmɒləsk/). Around 85, 000 extant species of molluscs are recognized.

Detailed explanation-4: -Soft-bodied invertebrates, mollusks include slugs, snails, octopuses, squid, clams, and mussels. Most mollusks have SHELLS to protect them.

Detailed explanation-5: -Bivalves are mollusks with two shells such as clams and oysters. Univalves are animals with one shell such as a snail. Mollusks without shells include squid, banana slugs, and octopi.