BIOL 2030 Lecture Notes - Lecture 9: External Fertilization, Protractor, Bait Fish
Document Summary
Mollusca large and diverse phylum of soft-bodied, usually unsegmented, coelomate animals, many of which live enclosed in a ahrd shell. They include the classes gastropoda (e. g. winkles, whelks, slugs, nails, se slugs), bivalvia (e. g. They include the classes gastropoda (e. g. winkles, whelks, slugs, nails, se slugs), bivalvia (e. g. clams, cockles), and other smaller classes of shells, and the the cephalopoda (nautilus, squids, and octopuses). The coelom is small and the main body cavity is a blood-filled haemocoel. Molluscs have a heart and blood system, and well-developed sense organs and nervous system, esp. in the cephalopoda. Matle fold of soft tissue underlying shell in molluscs, barnacles and brachiopods, and which usually encloses a space, the matle cavity, between it and the body proper. Radula short, broad organ with rows of chitonous teeth in mouth of most gastropod molluscs. Ctenidia a comblike structure, such as the respiratory apparatus of a mollusc. Nephridiopore external opening of excretory organs (nephridia) in invertebrates.
