Phylum Mollusca

Glossary of key terms related to Phylum Mollusca, covering classes, structures, and physiological processes.

Mollusca

The second largest phylum in the animal kingdom, characterized by soft-bodied animals with a calcareous shell.

Gastropoda

A class within Phylum Mollusca that includes snails and slugs, known for their diverse marine and terrestrial species.

Bivalvia

A class within Phylum Mollusca that includes clams, mussels, oysters, and scallops, characterized by two-part shells.

Cephalopoda

A class within Phylum Mollusca that includes squid and octopus, known for their advanced nervous systems and ability to change color.

Trochophore

A free-swimming larval stage in the development of many mollusks.

Radula

A feeding structure in mollusks, consisting of a band of teeth used to scrape food.

Mantle

Specialized tissue in mollusks that secretes the calcareous shell.

Counter-current flow

A mechanism in gills where blood flows in the opposite direction to water, maximizing oxygen absorption.

Nacreous layer

The inner layer of a mollusk shell, also known as mother of pearl, made of sheets of calcium carbonate.

Chitons

Members of the class Polyplacophora, known for their eight overlapping shells.