Phylum Porifera - Pore bearing animal.* Porifera are the
simplest multicellular animals.Example: SpongeSponge- Sponges are
composed of tiny needle like structures called Spicules.
Phylum Cnidaria - There are two general body forms found among
cnidarians.*Polyp body form - It is cylindrical, with a mouth and
tentacles at the upper open head.Example: Corals, Hydras , and Sea
anemone*Medusa body form - Shaped like an upside down bowl, with
the mouth and tentacles facing downward. Example: Jellyfish
Phylum Platyhelminthes - Flatworms or Phylum Platyhelminthes are
the simplest invertebrate group with definite head and tail
regoins.Example: Planaria, Flukes, and Tapeworms.
Phylum Nematoda Roundworms have elongated cylindrical bodies
that are tapered at both ends and covered by a tough
cuticleTrichina infects humans when they eat pork that has not been
cooked well.Filaria worms can cause a disease known as
elephantiasis.Pinworms are one of the most common parasitic
roundworms that infect childrenHookworms commonly infect people who
walk barefoot*Phylum Annelida Their bodies are divided into
segments with a ringed appearance.*Setae help the worm move through
soil.Example: Earth worms and Leaches
