Presentation on theme: "Cnidarians (Coelenterates). Phylum Cnidaria (Coelenterata) Class Hydrozoa = Hydra POLYP body form = “vase shaped” ; sessile Most live in colonies. 1 of."— Presentation transcript:
Phylum Cnidaria (Coelenterata) Class Anthozoa: “Flower Animals” –6,100 different species –Sea Anemones, Corals –Coral Reef = 30 degrees North or South of the equator, shallow water for photosynthetic algae that live in symbiosis with coral
Major Characteristics Body Plan: Hollow, 2 layered sac Body Cavity: Endoderm, Mesoglea (jelly like), Ectoderm Symmetry: Radial - pull in food from all around Cell Specialization: No Organs, Nematocysts = harpoon like stinging cells; neurotoxins cause paralysis
Life Support Processes Absorption: Gastroderm; directly into the body wall Feeding: tentacles pull food into the mouth; they are carnivores Digestion: Gastroderm (endoderm), food vacuoles in cells Respiration & Circulation: Gastrovascular inner cavity
Life Support Processes Excretion: Mouth opening, diffusion Secretion: sticky base for attachment Response: Nerve Net - contractile fibers in the epidermis; Ocelli - detects light Movement: contractile fibers; tumble motion through the water Reproduction: Asexual = budding; sexual = hermaphrodite (no self fertilization)
The largest jellyfish is the Arctic Giant Jellyfish: it can have a diameter over 8 ft. with tentacles stretching as long as 120 ft. The most venomous jellyfish is the Australian Sea Wasp; death can occur within 1-3 minutes. The Great Barrier Reef is the worlds largest stony coral structure stretching for 1,260 miles off Northeast Australia.