BIOL 305 Lecture Notes - Deuterostome, Bipinnaria, Tunicate

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 305
• Professor: Virginie Millien

Document Summary

Concentrating ingested organisms that are smaller than you is difficult: you can trap them with a sticky trap with cilia and mucous (eg. lophophorates, you can rake them to sort out the larger particles (eg. barnacles, you can strain them with perforations such that edible bits stay in and water flows out. Larval development: bipinnaria, to brachiolaria (have longer arms that do not correspond to arms of the adult, to late brachiolaria (one end develops more and the rest is sloughed off, at this point become pentaradially symmetrically. We often think of the evolution as the process of developing complexity for increased locomotive ease: echinoderms have lost all of this complexity, bilateral symmetry, segmentation, brain/central nervous system, vascular system, segmentation, eyes, gill slits, excretory system all lost, they"ve even done their best to lose their reproductive they just excrete gametes into the sea.