Cnidaria (jellyfish/squishy and corals and anemones) Matthew, Dohn, Tuckah

Cnidaria!!!! Includes hydras, corals, jellies, and anenomes All have cnidocytes http://z.about.com/d/animals/1/0/J/U/cnidarian1.jpg Tucker Chambers http://www.wrobelphoto.com/GelatinousZooplankton/Hydromedusae/Popup189.jpg

Some quick basics are sessile or floating Have two forms—polyp and medusa Tucker Chambers http://biology.unm.edu/ccouncil/Biology_203/Images/SimpleAnimals/cnidariaDiagram.jpeg

Scyphozoans Jellies Live mostly as medusae Tucker Chambers http://www.afrmc.org/images/jellyfish.jpg Tucker Chambers http://lesleehorner.files.wordpress.com/2009/12/jellyfish2.jpg

Anthozoans Sea anemones and coral Live only as polyps (sessile) http://library.thinkquest.org/07aug/01713/images/Brain_coral.jpg http://library.thinkquest.org/05aug/01819/Images/Sea%20Anemone.jpg Sea anemones and coral Live only as polyps (sessile) http://www.treehugger.com/dying-coral-frozen.jpg http://epaper.kek.jp/f05/PHOTOS/5_TOURS/5_004.JPG Tucker Chambers

Hydrozoans Very simple Found in fresh water Alternate between polyp and medusa stage http://www.ucmp.berkeley.edu/cnidaria/hydra1.gif Tucker Chambers http://library.thinkquest.org/26153/marine/sketch/600.jpg

Cubazoan's “Box Jellies” or “Sea Wasps” Have complex eyes along edge of medusae http://www.zoologie-online.de/Systematik/Metazoa/Cnidaria/Cubozoa/Carybdea.jpg Tucker Chambers http://www.jyi.org/articleimages/189/originals/img0.jpg

Body Cavity Acoelomates Tucker Chambers http://biology.unm.edu/ccouncil/Biology_203/Images/SimpleAnimals/cnidariaDiagram.jpeg

Body Symmetry Radial Symmetry Tucker Chambers http://www.dnr.sc.gov/marine/pub/seascience/images/undrview.gif

Circulatory System None!  Dory: I spy something pink and squishy that lacks a circulatory system! Marlin: Let me guess… a Cnidarian! http://www.the-reel-mccoy.com/movies/2003/images/FindingNemo3.jpg Matt Maneval

Digestive System Digestive or gastrovascular cavity open at one end. Captures animals with nematocysts on tentacles. http://www.advancedaquarist.com/2007/2/fish_album/polyp.jpg Matt Maneval

Excretory System None. Dory: They don’t have excretory systems? Gross. Marlin: That’s just wrong. http://www.bfi.org.uk/features/ultimatefilm/chart/images/185/56_finding_nemo.jpg Matt Maneval

Locomotion/Musculature Medusae swim by undulations of the bell body. Polyps are sessile. http://www.infoplease.com/images/ESCI294CNIDAR007.jpg Matt Maneval

Reproductive Cycles Hydrozans reproduce asexually by budding, the pinching off of outgrowths, when conditions are favorable. Hydrozans reproduce sexually in poor conditions by making resistant zygotes that remain dormant until conditions improve. Dan McKinney

Sensory Structures Most Cnidaria have simple sensory structues distributed throughout their bodies. Some, such as Cubazoans, have complex eyes embedded on the tips of their tentacles for catching prey. A Box Jellyfish http://www.ntnews.com.au/article/2008/12/13/21641_ntnews.html Dan McKinney

Skeletal System Cnidaria's lack bone structure. Most are supported by water swelling in their digestive cavity or water filled cells. Coral secretes calcium carbonate exoskeletons, which when dead form coral reefs. http://www.bloodydecks.com/forums/northern-california-inshore-offshore-reports/147737-ft-bragg.html

Gas Exchange Cnidarian species exchange gas through simple diffusion in and out of the cells. Dan McKinney http://www.aloha.com/~lifeguards/chironexfleckeri.jpg

Special “Powers” Cnidarians use poisonous tentacles to capture and kill their prey. These are called nematocysts. The Box Jelly Fish is so poisonous that one sting has enough venom to kill 60 men. http://lifeinthefastlane.com/2008/12/box-jellyfish-chironex-fleckeri/ Dan McKinney

Question 1 Do hydrozoans spend most of their life in Polyp Medusa Alternate between life cycles Matt Maneval

Correct Answer: C. Hydrozoans alternate between polyp and medusa throughout their life. Matt Maneval

Question 2 How do hydrozoans reproduce? Sexually Asexually Sexually and Asexually, depending on conditions. Matt Maneval

Correct Answer: C. Hydrozoans reproduce sexually and asexually, depending on the conditions. Matt Maneval http://animaldiversity.ummz.umich.edu/site/resources/Grzimek_inverts/Hydrozoa/v01_id118_con_hydanat.jpg/medium.jpg

Question 3 What classification do Sea Anemones fall under? Anthozoans Scyphozoans Hydrozoans Cubozoans Dan McKinney

Correct Answer: A, Anthozoans Matt Maneval

Question 4 Which of these are only sessile? Anthozoans Hydrozoans Scyphozoans Cubozoans Dan McKinney

Correct Answer: A, Anthozoans are only sessile. http://www.anthozoa.com/Photos/Welcome/Anthozoans.jpg Dan McKinney