Phylum Mollusca Flashcards
Phylum Mollusca
The phylum of snails, clams, and mussels
Bivalvia
The class of mollusks whose members have a 2-valved hinged shell, are usually filter-feeders, and lack a distinct head.
Cephalopoda
The class of mollusks whose members have a foot modified into a circle of tentacles and a siphon.
Chromatophore
Cells containing pigment that, through contraction and expansion, produces temporary color changes.
Closed Circulatory System
A circulatory system in an animal in which blood is confined to vessels throughout its circuit.
Coelom
A fluid-filled body cavity lined by mesoderm.
Gastropoda
A large class of mollusks which includes snails, slugs, and whelks. They have a large muscular foot for movement and a single asymmetrical spiral shell.
Mantle
The dorsal wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.
Mantle Cavity
The cavity between the mantle and the body proper of a mollusk or brachiopod in which the respiratory system lie.
Nephridium
A tubuale open to the exterior that acts as an organ of excretion or osmoregulation.
Open Circulatory System
Blood is pumped by a heart into the body cavities, where tissues are surrounded by the blood.
Operculum
A covering flap in animals, such as a gill cover.
Radula
A structure of tiny teeth used for scraping food particles off a surface and drawing them into the mouth.
Torsion
The rotation of the visceral mass, mantle, and shell 180 degrees with respect to the head and foot of the gastropod.
Trochophore
A ciliate, free-swimming larva common to several groups of invertebrates, as many mollusks and rotifers.
