Concept 33.1  Sponges are sessile and have a porous body and choanocytes	33.01
 Concept 33.2  Cnidarians have radial symmetry, a gastrovascular cavity, and cnidocytes	33.02
 Concept 33.3  Most animals have bilateral symmetry	33.03
 Concept 33.4  Molluscs have a muscular foot, a visceral mass, and a mantle	33.04
 Concept 33.5  Annelids are segmented worms	33.05
 Concept 33.6  Nematodes are nonsegmented pseudocoelomates covered by a tough cuticle	33.06
 Concept 33.7  Arthropods are segmented coelomates that have an exoskeleton and jointed appendages	33.07
 Concept 33.8 Echinoderms and chordates are deuterostomes	33.08
Activity: Characteristics of Invertebrates	33&A
Investigation: How Are Insect Species Identified?	33&A
Video: Bee Pollinating	BeePollinating-V.html=BeePollinating-V.swf
Video: Butterfly Emerging	ButterflyEmerge-V.html=ButterflyEmerge-V.swf
Video: C. elegans Crawling	CElegansCrawl-V.html=CElegansCrawl-V.swf
Video: C. elegans Embryo Development (time-lapse)	CElegansEmbryo-V.html=CElegansEmbryo-V.swf
Video: Clownfish and Anemone	ClownfishAnemone-V.html=ClownfishAnemone-V.swf
Video: Coral Reef	CoralReef-V.html=CoralReef-V.swf
Video:  Earthworm Locomotion	EarthwormLocomot-V.html=EarthwormLocomot-V.swf
Video:  Echinoderm Tube Feet	EchinodermTubeFeet-V.html=EchinodermTubeFeet-V.swf
Video:  Hydra Budding	HydraBudding-V.html=HydraBudding-V.swf
Video:  Hydra Eating 	HydraEating-V.html=HydraEating-V.swf
Video:  Hydra Releasing Sperm	HydraSperm-V.html=HydraSperm-V.swf
Video: Jelly Swimming	JellySwimming-V.html=JellySwimming-V.swf
Video: Lobster Mouth Parts	LobsterMouthParts-V.html=LobsterMouthParts-V.swf
Video: Nudibranchs	Nudibranchs-V.html=Nudibranchs-V.swf
Video: Rotifer	Rotifer-V.html=Rotifer-V.swf
Video: Thimble Jellies	ThimbleJellies-V.html=ThimbleJellies-V.swf
Video:  Tubeworms	Tubeworms-V.html=Tubeworms-V.swf