Chapter 24 and 25 Sponges, Cnidarians, Flatworms, and Roundworms

Phylum Porifera (“pore-bearer”) ~Includes all sponges (grantia, scypha, & leucosolenia) Basketball sponge Cinachyra sponge

Knob sponge Simplest animals Simplest animals Asymmetrical Asymmetrical

Phylum Porifera  Aquatic  Sessile - can’t move from place to place  Filter feeders Red sponge Volcano sponge

Phylum Porifera  Reproduce both sexually and…  Asexually * Regeneration – * Regeneration – reattach reattach * Budding - grow * Budding - grow new sponges new sponges Dead man’s finger sponge

Phylum Porifera  Hermaphrodites - produce both eggs and sperm Sponge dumping gametes Phylum Porifera

 Osculum - opening on some sponges  Spicules - sharp, hard, needle- like structures - attachment

Phylum Cnidaria (“nettles” / tentacles) Includes jellyfishes, corals, sea anemones & hydras Brain coral Jellyfishes Green anemone

Phylum Cnidaria  Aquatic  Radial symmetry Flower pot coral Purple anemone

Phylum Cnidaria  Nerve net - a simple nervous system Sun coral Torch coral

 Nematocysts - tubes in tentacles - contains poison

 Gastrovascular cavity - primitive stomach

Monterey, CA

Phylum Cnidaria  Two basic body forms Polyp - tube shaped body Medusa - body shaped like an umbrella Medusa Red cauliflower coral Moon jelly

Club tipped anemone Pineapple coral Staghorn coral Sea anemone

Corals

Hydra releasing an egg Hydra releasing sperm Budding hydra Reproduce: Sexually - hermaphrodites Asexually - budding

PHYLUM: PLATYHELMINTHES (“flat worms”)  Includes: Tapeworms & liver flukes (Parasitic) Tapeworms & liver flukes (Parasitic) Planarians (Free-living) Planarians (Free-living)  Bilateral symmetry

(PHYLUM: PLATYHELMINTHES)  Some have eyespots  Scolex - head of a tapeworm  Proglottid - body part

LIFE CYCLES: May involve two or more hosts. (TAPEWORM LIFE CYCLE) Most have digestive systems Most have digestive systems Exception: Tapeworms

Life Cycle of a Liverfluke

PHYLUM: NEMATODA (“Thread” / Roundworms)

PHYLUM: NEMATODA  Includes: Ascaris (Roundworms) Ascaris (Roundworms) Pin worms Pin worms Trichina worms Trichina worms Hookworms Hookworms  The above are parasitic  Most are free-living

PHYLUM: NEMATODA  Bilateral symmetry  Some are hermaphrodites

LIFE CYCLE OF A ROUNDWORM

PARASITIC WORMS WORM HOW ACQUIRED INVADES Tapeworm / Roundworm Eating raw meat Intestines Hookworm Walking barefoot Lungs Liver fluke Eating raw fish Liver Trichina worm Eating raw pork Muscles