Flatworms had it FIRST!! _______________________ symmetry Directional motion = Cephalization = development of a __________________ bundle of nerve cells make up a pre-brain Nerves concentrated at ‘head end’ since sensory cells were concentrated at that end Sensory nerves formed bundles = ganglion Eyespots detect Auricles detect chemicals 2 ____________________ transmit info to rest of body

New Innovations in: Excretory System! cellular waste still removed by flame cells help regulate solute concentration Evolve in to the nephrons of Mammals kidney First

Flatworm Reproduction 1st ____________________fertilization Evolutionary advantage Hermaphrodites Evolutionary advantage = you can mate with any other member of your species that you can find! Asexual Reproduction =

Ancestral Traits cavity for digestion & circulation Mouth Respiration by

Classes of Flatworm 1) Free living 2) Flukes 3) Tapeworms

Swimmer’s Itch =Schistosoma

Tape Worms = Class Cestoda

Human Tape Worm Sources = Prevention

Round Worms! Phylum 1st Complete digestive tract = 1st Separate sexes

Round Worms = Phylum Nematoda 1st Animal with a body cavity = fake body cavity:

Types of body cavity (coelom) Acoelomate Pseudocoelomate Coelomate

Digestive Tract 1st Alimentary Canal = Evolutionary advantage