Earth Sciences 1083F/G Lecture 19: Lecture 19 - Survey of Invertebrates
25 Jan 2012
School
Department
Course
Professor
Document Summary
Lecture 19 survey of invertebrates y how do you make a metazoan: starts with a single protista (e. g. amoebas) y phylum protista, importance of chaonoflagellates: protists with a collared cells and a flagellum for movement. bilateran with a coelom can squeeze its internal fluids with body muscles. squeezing bulges the body wall at the weakest point, and can be used for burrowing. pumping could facilitate the transport of oxygen through the body without relying on the bathing of tissues in oxygenated water by diffusion through a thin ectoderm y meant they could develop exoskeletons: in protosomes . ectoderm and endoderm can be viewed as essentially solid, continuous layers. mesoderm more complicated, lines a fluid-filled body cavity called the coelom. within the coelom that internal organs other than the gut develop. found in protozomes like mollusks, annelid worms and arthropods.
