Phyla Cnidaria and Ctenophora= jellies, anemones, corals, hydrozoans and comb jellies
= Coelenterates
Coelenterate CharacteristicsRadial/biradial symmetry
Diploblastic
Majority marine
Benthic or planktonic
Solitary or colonial
Free swimming larvae
Cnidarian Body PlanEpidermis, gastrodermis& mesogleaPolymorphismPolypCylindrical, pedal disk orphysa, terminal mouthDactylo-, gono-, gastro-,siphonozooidsMedusaExumbrella, subumbrellaMarginal tentaclesManubriumReproductive stageMuscular system = notmesodermalNerve system = 2 nervenets
Cnidaria Body:Sensory/Defense Organs
Mechanoreceptors = hairlike, in area of cnidocytesRhopalia = variety of structuresStatocystsOcelli = pigment cup and eyes = in cubozoans, bell margin
Nematocysts in cnidocytes, damaging
Ctenophore Body Plan
Spherical to ovoid, intricate canal systemMouth at one pole, apical sense organ at the otherCtene rows extending from mouth to ASO = paddle like combPlates of fused ciliaEpidermis and gastrodermis separated by mesogleaSticky lasso cells (colloblasts), no nematocyst
mouthdigestivecavity
canal
canal
canal
canalcanal
canal
canalcanal
canal
canal
canal
canaltentacle tentacle
canal
Nutrition and Digestive System
http://www.youtube.com/watch?v=HheMqLyw1d8&feature=related
CarnivorousTrap prey or suspension feeders,nematocystsContractile tentacles,colloblasts
Symbiotic algae(particularly corals)
Digestion= extra- and intracellular
One digestive opening only, analpores
Waste diffusion and rosettes
Reproduction and LifecyclesSexualDioeciousHermaphroditicPlanula orcydippid
Strobilation
Asexuala. Buddingb. fissionc. Frustuled. Segmentation
Symbiosis and Interactions
1. Anemones and hermit crabs2. Nudibranchs3. Clownfish and anemone4. Zooxanthellae
Classification CnidariaAnthozoa Staurozoa Cubozoa Scyphozoa Hydrozoa
Polyp/medusaNo statocyst/rhopalia
True jelliesPolyp/medusa
Rhopalia
SmallEyes
Rhopalia
PolypMuscles
Medusa
Ctenophore ClassificationClass TentaculataOvoid bodiesContain tentacles
Class NudaConical bodiesNo feeding appendagesLarge pharynx with largecilia= create feeding currents