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 nematosystssensory receptionfood capturerespirationexcretion

~mesoglea functions inbody supportcements epithelianerve and muscle pathwaysdiffusion pathway

~endoderm = gastrodermis functions indigestionenzyme secretionfood uptakerespirationexcretion

Everting intracellular organelles (cnidae)~nematosysts = stining capsules

small hypodermic syringesvenom

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 dwellinganemones

nematocyst

Digestion is extracellular and intracellular

Skeletonhydrostatic- fluid filled, muscels operate against an

incompressable fluid

hard skeleton as with corals

Reproduction - ~metagenesis---alternation of generations

polyp or polyp colony = asexual stagemedusa = sexual stage

~Larva = planula~dioecious or monoecious

Classsification~class hydrozoa (hydra, hydroids, siphonophores, hydrocorals)

no mesentaries or septa in coelentrongastrodermis lacks nematocystshydromedusae have velum = a small shelf of tissue projecting

in from bell marginstructure

perisarc=non-living outer protective sheathcoenosarc=living tissue of hydrozoan within perisarchydrocaulus=stalk of colonythecate - where the stalk and polyps surrounded by

perisarchydrothecate=feeding polypgonotheca = reproductive polyp

athecate- only stalk surrounded by perisarc

Hydromedusae - free living, ‘pelagic’

Gonads visible

Aequoria

Hydra-common freshwater form

Hydra, budding

Obelia-thecate 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 jellyfishTetramerous - 4 parterNo velumGastrovascular cavity

gastric pouchesgastric filimentsgastrodermal nematocysts

ManubriumRhopalium = sensory organs

statocystchemosensory pitsocellus

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 characteristics-radial symmetrynematocysts

1. Tentacles2. Pharynx3. Siphonoglyph4. Gastrovascular cavity5. Primary septum6. secondary septum7.tertiary septum8. Acontia- nematocysts9. 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

Anthozoans- prostaglandins painkillers coral skeleton used in human bone

repair