radiate animals
DESCRIPTION
Radiate Animals. Cnidarians and Ctenophores. Radiates Are Eumetazoans. Radiates. Radial symmetry Tissue level organization Two germ layers Ectoderm and endoderm Nerve net (simple nervous system) Extracellular digestion. Cnidaria. Ctenophore. Radiate Phyla. Phylum Cnidaria. Two forms - PowerPoint PPT PresentationTRANSCRIPT
Radiate Animals
Cnidarians and Ctenophores
Radiates Are Eumetazoans
PhylumC nidaria
H ydra , je lly fish e tc ...
Phy lumC tenophoraC om b je llies
G rade R ad ia taR a dia l Sym etry
D iv is ion Pro tos tom ia D iv is ion D eu te ros tom ia
G rade B ila tera taB ila tera l Sym etry
Eum etazoaTrue T issue s
Radiates
• Radial symmetry• Tissue level organization• Two germ layers
– Ectoderm and endoderm• Nerve net (simple nervous system)• Extracellular digestion
Radiate Phyla
• Cnidaria • Ctenophore
Phylum Cnidaria
• Two forms– Polyp– Medusa
• Tentacles• Nematocyst
Polyp and Medusa Forms
Class Hydrozoa
• Mostly colonial• Polyp and medusa life cycle for most• Hydra – non colonial polyp stage only• Obelia – typical colony
– Chiton exoskeleton– Extracellular and intercellular digestion
Hydra
Hydra Tissue Structure
Obelia Life Cycle
Gonionemus
Class Scyphozoa
• Larger jellyfish• Not colonial• No vellum• Internal gastric pouches
– Radial canals lead to ring canal
Aurelia Life Cycle
Medusa
Strobilia
Class Anthozoa
• Subclasses– Zoantharia – anemones, hard coral– Alcyonaria – sea fans (soft coral)– Ceriantipatheria – tube anemone, horny coral
• Polyp form, no medusa stage• Partitioned gastrovascular cavity
Sea Anemone
Sea Anemone
Anemone Fish (Clown Fish)
Zoantharian Coral
• Calcium carbonate exoskeleton secreted externally from base
• Contain mutualistic zooxanthallae algae
• Live in colonies• Hexamerous symmetry
Coral Polyps
Alcyonarian Coral
• Octomerous symmetry
• Colonial• Can communicate
with members of colony through tubes call solenia
• Endoskeleton composed of spicules and protein and secreted within mesoglea
Soft Corals
Phylum Ctenophora
• Comb Jellies• Move using cilia
– Comb plates• Do not have nematocysts
– Colloblasts capture food
Comb Jelly Tentacle
Comb Jelly Structure
Comb Jelly Cilia
Predatory Comb Jellies Approaching Prey
Predatory Comb Jelly Engulfing a Comb Jelly
Comb Jelly After a Meal