BIOL 2003 Lecture Notes - Lecture 9: Circulatory System, Odontophore, Solenogastres
8 Jan 2018
School
Department
Course
Professor
Document Summary
Internal organs: digestive, excretory, reproductive, and respiratory: mantle and mantle cavity: mantle=the skin, can have muscles or chemoreceptors. Makes the shell: mantle cavity = open to the world, excretion (metabolic and digestive), respiration, reproduction. Shell: made by the outer layer of mantle: periostracum: outer organic layer (resistant protein conchiolin), part that peels off, prismatic layer (biggest): calcium carbonate stacks, nacre: continuously thickens, calcium carbonate + protein sheets, where pearls form. Natural pearls are stronger and more layered than cultured pearl. Foot: used for locomotion and attachment, found on ventral side of the body. Reproduction system of molluscs: never asexual, dioecious (separate male or female) or monoecious (male and female, trochophore larvae in most, veliger larvae common (aquatic bivalves and gastropods) Classes caudofoveata and solenogastres (the aplacophorans): worm-like and shell-less, calcareous scales/ spicules, marine detrital/microorganism consumers- burrowers, reduced head, no foot.
