Protostomes and Mollusca Overview

These flashcards cover key vocabulary and concepts related to Protostomes, Mollusca, and their classifications.

Protostomes

A group of animals characterized by a specific pattern of early embryonic development including spiral cleavage.

Lophotrochozoa

A clade within protostomes that includes organisms such as mollusks and annelids, often characterized by the presence of a trochophore larva.

Ecdysozoa

A clade of protostomes that includes animals that molt their exoskeleton, such as arthropods and nematodes.

Trochophore

A free-swimming larval stage characteristic of many lophotrochozoans.

Radula

A rasping, tongue-like structure used by most mollusks for feeding.

Mollusca

A phylum of invertebrate animals that includes snails, clams, and octopuses, known for their diverse body forms and structures.

Coelom

A body cavity lined by tissue derived from mesoderm, highly reduced in mollusks.

Mantle

A thick epidermal sheet in mollusks that bounds the mantle cavity and secretes the shell.

Ctenidia

Gills found in aquatic mollusks, involved in both gas exchange and filter feeding.

Annelida

A phylum of segmented worms that includes earthworms and leeches, characterized by repeating body segments.

Metamerism

The segmentation of body structures in annelids that allows for specialization of body segments.

Chelicerata

A class of arthropods that includes spiders and scorpions, characterized by the presence of chelicerae.

Crustacea

A class of arthropods that includes crabs and shrimp, typically with two pairs of antennae and two body regions.

Hexapoda

A class of arthropods that includes insects, characterized by three body segments: head, thorax, and abdomen.

Myriapoda

A class of arthropods that includes centipedes and millipedes, characterized by a segmented body and numerous legs.

Bivalvia

A class of mollusks that includes clams and oysters, characterized by two hinged shells.

Cephalopoda

A class of mollusks that includes squids and octopuses, known for their intelligence and complex behaviors.

Internal Fertilization

A reproductive strategy where fertilization occurs inside the female's body, as seen in many mollusks.

Exoskeleton

A hard external skeleton that provides protection and support, characteristic of many arthropods.

Ecdysis

The process of molting in arthropods, allowing for growth.