Parazoano true tissues

Eumetazoa

Multicellularity

Radiata Bilateria

QUIZ (CHAMPACA)

1. True or False: Jellyfishes have no nervous system.

2. What are the 2 stages of the life cycle of jellyfishes?

3. What is the term used to describe the two-tissue layer that Cnidarians possess?

4. Give one class under this Phylum

5. Give ecological significance of Cnidarians.

• Gr. “nettle”

• cnidocytes with nematocysts

• previously “Coelenterata” with the Ctenophora(coel + enteron)

• 10 000 sp.

PHYLUM CNIDARIAPHYLUM CNIDARIASTINGING ANIMALSSTINGING ANIMALS

http://farm4.static.flickr.com/3085/2832954307_dc57ebb1a6.jpg, http://news.nationalgeographic.com/news/2006/01/images/060119_jellyfish.jpg, http://www.seasky.org/wallpaper/assets/wallpaper_sea/anemones-1280.jpg, http://www.aquariumdomain.com/images/corals/closedBrainCoral1.jpg

FORM AND FORM AND FUNCTIONFUNCTIONDIMORPHIC BODY PLANDIMORPHIC BODY PLAN

• radially-symmetric

• diploblastic• 2-layered body wall (epidermis +

gastrodermis)• gelatinous mesoglea

• gastrovascular cavity (GVC)• incomplete gut• digestive sac with only one opening

http://www.reefed.edu.au/__data/assets/image/0005/17987/polypdiagram.gif, http://3.bp.blogspot.com/-GHG4p2wPVPs/TenLrQE0cyI/AAAAAAAAA_s/YZiq_lfYItM/s1600/10a.JPG,

FORM AND FUNCTION: FORM AND FUNCTION: FEEDINGFEEDING

http://arayalacy.files.wordpress.com/2011/11/digesthydra2.jpg, http://www.bio.miami.edu/dana/pix/cnidocyte.gif

• predatory

• extracellular digestion in GVC intracellular within cells of gastrodermis

• circulation through diffusion

FORM AND FUNCTION: FORM AND FUNCTION: RESPONSERESPONSE

http://media-3.web.britannica.com/eb-media/35/73335-004-9E50A397.jpg

FORM AND FUNCTION: FORM AND FUNCTION: MOVEMENTMOVEMENT

Polyps: hydrostatic skeleton

Contractile fibers (not true muscle tissues) + H2O in GVC

Medusas: jet propulsion

Fibers contract medusa closes H2O forced out forward movement

FORM AND FUNCTION: FORM AND FUNCTION: REPRODUCTIONREPRODUCTION

ASEXUAL THROUGH BUDDINGSEXUAL THROUGH SYNCHRONIZED

RELEASE OF GAMETES

http://www.aaskolnick.com/hydra3.jpg

, http://www.walldesk.net/pdp/1024/17/14/-Sea-Anemone.jpg

, http://www1.american.edu/ted/images4/braw3.jpg

, http://www.oceanwideimages.com/images/2475/large/box-jellyfish-24M1211-16.jpg

ECOLOGYECOLOGY

Coral reefs

•budding produces new polyps, new polyps lay down new limestone

• growth rate, lifespan

http://www.cdnn.info/eco/e040701a/e040701a.html

http://i2.cdn.turner.com/cnn/dam/assets/130201123703-01-guardian-0201-horizontal-gallery.jpg

IMPORTANCEIMPORTANCE

Coral reefs

•symbiotic relationships with other plantlike protists

•animal habitat

•protects land from wave action

•tourism

•medical research

http://www.cdnn.info/eco/e040701a/e040701a.html

IMPORTANCEIMPORTANCE

Distribution of corals

determined by:

•temperature

•water depth

•light intensity

Problems of corals:

•Human activity

•Coral bleaching

http://ih.constantcontact.com/fs113/1108454596610/img/168.jpg?a=1111854027677 , http://www.breef.org/oldsite/Portals/0/coralmcavbleached%20Sandy%20for%20web.jpg, http://serc.carleton.edu/images/eslabs/corals/coral_bleaching_diagram.gif