Presentation on theme: "Cnidarians By Siobhan Curtis. What is a Cnidarian? Greek from the word “Knide” meaning “Nettle” because they can sting. 10,000 Different species found."— Presentation transcript:
What is a Cnidarian? Greek from the word “Knide” meaning “Nettle” because they can sting. 10,000 Different species found in aquatic and mostly marine environments.
Description: 2 basic types: Swimming Medusae ( free swimming sexual form) Sessile polyps Both body types are radially symmetrical With mouths surrounded by tentacles. Bodies consist of mesoglea (a non living jelly like Substance) sandwiched between two layers of Epithelium that are 1 cell thick.
Life History Generally occupy open marine water. Feed on Plankton( heavy factors in which to keep the plankton population in control.), Small Crustaceans, Fish eggs, Fish, and other Jelly fish. Although they are preyed on by: Tuna, Sharks, Sea Turtles, Swordfish, and Salmon Jellyfish are plankton, so they are important for keeping balance in the aquatic ecosystem.
LIFE CYCLE YAY!!!!!!! FERTILIZED EGG >PLANULA LARVA ( a free swimming coelenterate larva with a flattened, ciliated, solid body) >POLYP>POLYP TRANSFORMING>YOUNG MESDUSA> JELLY LIKE MESOGLEA During their life cycle they experience alterations of generations. EX: The Medusae reproduces sexually and the polyp reproduces asexually.
More Sexy Time: 1. Male Medusae release sperm from their mouth opening located on the underside of the bell.
PUGET SOUND HAS JELLIES WHAT!!!!!!! Puget sound was so abundant with jellies in 2003 it filled 80- 90% of all biomass.