Phylum Cnidaria Coelenterata Cnido nettle Jellyfish not real

Phylum Cnidaria - Coelenterata (Cnido = nettle)

Jellyfish - not real fish

Blind sac- a bag with only one opening Diploblastic ~epidermis functions in protection, mucus, flagella and nematosysts sensory reception food capture respiration excretion ~mesoglea functions in body support cements epithelia nerve and muscle pathways diffusion pathway

~endoderm = gastrodermis functions in digestion enzyme secretion food uptake respiration excretion

Everting intracellular organelles (cnidae) ~nematosysts = stining capsules small hypodermic syringes venom neurotoxic (nerves) myotoxic (muscles) hemolytic (destroys RBC’s) necrotic (digests tissue) not all of the 30 types inject venom ~spirocysts - adhesive organslles anmones, corals and the like ~ptychocysts - used in the construction of tubes of tube dwelling anemones

nematocyst

Digestion is extracellular and intracellular Skeleton hydrostatic- fluid filled, muscels operate against an incompressable fluid hard skeleton as with corals Reproduction ~metagenesis---alternation of generations polyp or polyp colony = asexual stage medusa = sexual stage

~Larva = planula ~dioecious or monoecious

Classsification ~class hydrozoa (hydra, hydroids, siphonophores, hydrocorals) no mesentaries or septa in coelentron gastrodermis lacks nematocysts hydromedusae have velum = a small shelf of tissue projecting in from bell margin structure perisarc=non-living outer protective sheath coenosarc=living tissue of hydrozoan within perisarc hydrocaulus=stalk of colony thecate - where the stalk and polyps surrounded by perisarc hydrothecate=feeding polyp gonotheca = reproductive polyp athecate- only stalk surrounded by perisarc

Hydromedusae - free living, ‘pelagic’

Gonads visible

Aequoria

Hydra-common freshwater form

Hydra, budding

Obeliathecate marine hydroid

Hydractinia symbiotic, athecate marine hydroid Pagurus

Velella velella - by the wind sailor

Fire coral

hydrocoral

Physalia - Portugese man of war

~class Scyphozoa--true jellyfish Tetramerous - 4 parter No velum Gastrovascular cavity gastric pouches gastric filiments gastrodermal nematocysts Manubrium Rhopalium = sensory organs statocyst chemosensory pits ocellus Most dioeceous - planula Diversity

cassiopea

Chrysaora

Aurelia - moon jelly

Pelagia

~Class cubozoa - box jellies Chironex = sea wasp

~Class Anthozoa- anemones, true corals, sea fans, sea pens, soft corals anemones, zoanthids General characteristicsradial symmetry nematocysts 1. Tentacles 2. Pharynx 3. Siphonoglyph 4. Gastrovascular cavity 5. Primary septum 6. secondary septum 7. tertiary septum 8. Acontia- nematocysts 9. Pedal disc

Mouth K. O. D.

Aggregating anemone - Anthopleura elegantissima

A. xanthogrammica. in the surf zone

A. xanthogrammica…closed with sand

Malu-movement

Hermassinda crasicornis and red anemones

Clown fish

Octocorals - 8 parter radial symmetry-skeleton-colonial Soft corals

Sea pen

Sea fan. Also sea pansies, sea whils Anthozoansprostaglandins painkillers coral skeleton used in human bone repair