CNIDARIACNIDARIA

CharacteristicsCharacteristics

Class Scyphozoa- Class Scyphozoa- Jellyfish- medusa formJellyfish- medusa form

Class Antozoa- corals, sea Class Antozoa- corals, sea anemones- polyp formanemones- polyp form

Class Hydrozoa- HydrasClass Hydrozoa- Hydras TentaclesTentacles 2 body plans:2 body plans: Polyp- attached to ocean Polyp- attached to ocean

floor, mouth opens up, floor, mouth opens up, tentacles surround mouthtentacles surround mouth

CharacteristicsCharacteristics

Medusa- free Medusa- free floating/swimming floating/swimming form, mouth opens form, mouth opens down, tentacles trail down, tentacles trail down, bell-shapeddown, bell-shaped

No organsNo organs Movement- jellyfish Movement- jellyfish

swim, anemones move swim, anemones move slowly along ocean slowly along ocean floorfloor

AnatomyAnatomy

Gas exchange Gas exchange happens at cell levelhappens at cell level

No muscle cells, No muscle cells, skeleton, or circulationskeleton, or circulation

Nerve NetNerve Net Epidermis cells create Epidermis cells create

“skin”“skin” No excretory systemNo excretory system

AnatomyAnatomy

Tentacles have Tentacles have nematocysts – stinging nematocysts – stinging cellscells

Central hollow body Central hollow body cavitycavity

Radial symmetryRadial symmetry AcoelomatesAcoelomates

FeedingFeeding

Uses stinging ability to Uses stinging ability to capture foodcapture food

Prey is stung and Prey is stung and brought to mouth by brought to mouth by tentaclestentacles

Digested in central Digested in central body cavitybody cavity

Niche: Predators, Niche: Predators, carnivorescarnivores

ReproductionReproduction

Reproduction is both Reproduction is both sexual and asexualsexual and asexual

Asexual- budding by Asexual- budding by hydras, coral, sea hydras, coral, sea anemonesanemones

Sexual- jellyfish have Sexual- jellyfish have both sexes. Females both sexes. Females produce eggs, males produce eggs, males produce spermproduce sperm

Life CycleLife Cycle

Fertilized egg turns Fertilized egg turns into larvaeinto larvae

Larvae settles on Larvae settles on ocean floorocean floor

Polyp developsPolyp develops Medusa buds off of Medusa buds off of

polyppolyp Medusa reproduces Medusa reproduces

sexually to form sexually to form fertilized eggfertilized egg

HabitatHabitat

Marine/ Ocean habitatMarine/ Ocean habitat Polyp form lives on Polyp form lives on

ocean floorocean floor Medusa form swims Medusa form swims

freely in open waterfreely in open water What are some biotic What are some biotic

and abiotic factors?and abiotic factors?

Colony LifeColony Life

Corals reefs- coral polyp Corals reefs- coral polyp attaches to rock or ocean attaches to rock or ocean floor, secretes calcium floor, secretes calcium carbonate (CaCOcarbonate (CaCO33) which ) which

is a hard skeleton. Then it is a hard skeleton. Then it reproduces asexually. reproduces asexually. Offspring attach on top of Offspring attach on top of same hard skeleton and same hard skeleton and cycle goes on. This is how cycle goes on. This is how a coral reef is builta coral reef is built

Colony LifeColony Life

Portuguese Man-o-Portuguese Man-o-WarWar

Is really over 1000 Is really over 1000 polyps living together polyps living together

Some sting, some Some sting, some digest, some produce digest, some produce sex cellssex cells

HydraHydra

Stays in polyp form Stays in polyp form throughout lifethroughout life

Only freshwater Only freshwater cnidarianscnidarians

Predators- prey on Predators- prey on small invertebratessmall invertebrates

Named after Greek Named after Greek mythology serpent-like mythology serpent-like creature with many creature with many headsheads

AdaptationsAdaptations

Regeneration of body Regeneration of body partsparts

Anemones have strong Anemones have strong adhesion in strong wavesadhesion in strong waves

Asexual reproduction – Asexual reproduction – can colonize a large area can colonize a large area quicklyquickly

Anemone can contract to a Anemone can contract to a tight ball to prevent drying tight ball to prevent drying out in low tideout in low tide