Cnidaria Cnidaria Hydra, Jellyfish, Coral, & Sea Anemones

CnidariaCnidariaHydra, Jellyfish, Coral, & Sea Hydra, Jellyfish, Coral, & Sea

AnemonesAnemones

Phylum CnidariaPhylum CnidariaSomeSome examples of Cnidaria are:examples of Cnidaria are:

• Sea anemones and Corals-Sea anemones and Corals- Anthozoa Anthozoa

• Hydra-Hydra- Hydrozoa Hydrozoa

• Jelly fish-Jelly fish- Scyphozoa Scyphozoa

• Ctenophores-Ctenophores- non stinging non stinging Cnidarians:Cnidarians: Comb JellyComb Jelly

AnatomyAnatomyA. A. PolymorphismPolymorphism- Cnidarians - Cnidarians

have more than one body have more than one body form:form:

1. 1. PolypPolyp

2. 2. MedusaMedusa

Polyp FormPolyp Form• Tube with tentacles Tube with tentacles

around the moutharound the mouth

• SessileSessile

Coral polyp

Polyp (sea anemone)Polyp (sea anemone)

Polyp (Hydra)Polyp (Hydra)

Medusa FormMedusa Form• Umbrella shapeUmbrella shape

• Tentacles around mouthTentacles around mouth

• Motile, Free-swimmingMotile, Free-swimming

TentaclesTentacles• Have Have

nematocysts nematocysts

(stinging cells)(stinging cells)

• Coiled thread Coiled thread discharges discharges

like a harpoonlike a harpoon

• Contains Contains neurotoxinneurotoxin

• Paralyzes preyParalyzes prey Discharged nematocyst

Level of Level of OrganizationOrganization

A. Cnidarians have tissuesA. Cnidarians have tissues

B. No organsB. No organs

C. Most Cnidarians have C. Most Cnidarians have Radial SymmetryRadial Symmetry

Radial SymmetryRadial Symmetry

Compass jellyfish

RadialRadial

HabitatHabitatAquatic:Aquatic:

1. Most 1. Most MarineMarine

2. Few 2. Few fresh-waterfresh-water

FeedingFeeding

A. Carnivores A. Carnivores

(predators)(predators)

B. Process of feedingB. Process of feeding

1. Tentacles sting prey with1. Tentacles sting prey with

nematocystsnematocysts

2. Tentacles grab prey2. Tentacles grab prey

3. Prey pulled into mouth3. Prey pulled into mouth

Lion’s mane eats another jelly

Process of feedingProcess of feeding

4. Prey stuffed into 4. Prey stuffed into gastro-gastro-vascularvascular cavitycavity (GVC)* (GVC)*

5. GVC makes 5. GVC makes enzymesenzymes, extra-, extra-cellular digestioncellular digestion

6. Undigested food back out 6. Undigested food back out mouthmouth

**incomplete digestive tract (no incomplete digestive tract (no anus)anus)

Lion’s mane jellyfish eating Lion’s mane jellyfish eating

RespirationRespiration• Via diffusion Via diffusion

• Body is two cell layers Body is two cell layers

thickthick

Internal TransportInternal Transport• Via diffusionVia diffusion

ExcretionExcretion

• Via diffusionVia diffusion

ResponseResponseA.A. No nervous systemNo nervous system

B.B. Nerve net around mouthNerve net around mouth

LocomotionLocomotion

A.A. Medusa- Medusa- motilemotile, free-swimming, free-swimming

B.B. Polyps- Polyps- sessilesessile,, attached to hard attached to hard substratesubstrate

Exceptions: Exceptions:

1. Hydra tumbles on tentacles1. Hydra tumbles on tentacles

2. Sea anemones glide on pedal 2. Sea anemones glide on pedal discdisc

ReproductionReproduction

1. 1. Asexual Asexual buddingbudding2. 2. SexualSexual

a. Medusae release sperm & eggsa. Medusae release sperm & eggs b. Larvae are free-swimmingb. Larvae are free-swimming

Ecological RoleEcological RoleA.A. Predators and preyPredators and prey

B.B. Neurotoxins in medical researchNeurotoxins in medical research

C.C. Coral – jewelry, building, reefs Coral – jewelry, building, reefs (surfing!)(surfing!)

D.D. Coral reefs - habitat for manyCoral reefs - habitat for many

-great biodiversity-great biodiversity

- protect coastline- protect coastline

E.E. Symbiosis with other organisms Symbiosis with other organisms

Class Anthozoa: Sea Class Anthozoa: Sea AnemonesAnemones

Sea Anemones (with sea Sea Anemones (with sea urchins)urchins)

Sea Anemones Clown fish with Sea Anemones Clown fish with sea anemonesea anemone

Clown fish & eggs with sea Clown fish & eggs with sea anemone anemone

Clown fish with sea Clown fish with sea anemoneanemone

Giant Sea AnemoneGiant Sea Anemone

Rosy Sea AnemoneRosy Sea Anemone

Class Anthozoa: CoralsClass Anthozoa: Corals

Brain CoralBrain Coral

CoralCoral

Colt CoralColt Coral

Elkhorn CoralElkhorn Coral

Cabbage CoralCabbage Coral

Flower CoralFlower Coral

Feather CoralFeather Coral

Gorgonian Fan CoralGorgonian Fan Coral

Lamellina CoralLamellina Coral

Sun CoralSun Coral

Subergorgia CoralSubergorgia Coral

Soft CoralSoft Coral

Sea PenSea Pen

Sea FanSea Fan

Sea PlumeSea Plume

Class Hydrozoa: Green Class Hydrozoa: Green HydraHydra

HydraHydra

Brown Hydra with budsBrown Hydra with buds

Brown Hydra eatingBrown Hydra eating

Hydra eating DaphniaHydra eating Daphnia

• Hydra eats DaphniaHydra eats Daphnia

Class Scyphozoa: True Class Scyphozoa: True JellyfishJellyfish

Fried egg jelly

JellyfishJellyfish

JellyfishJellyfish

Red-eyed medusa

JellyfishJellyfish

JellyfishJellyfish

JellyfishJellyfish

Lion’s mane

JellyfishJellyfish

Purple lion’s mane

Upside down Jelly fishUpside down Jelly fish

Upside down Jelly fishUpside down Jelly fish

Sea NettleSea Nettle

Jelly and diverJelly and diver

Giant Jelly off Coast of JapanGiant Jelly off Coast of Japan

Beached Jelly fishBeached Jelly fish

Jelly fish HumorJelly fish Humor

Portuguese Portuguese Man 0’ WarMan 0’ War

(a (a Hydrozoan), Hydrozoan), NOT a true NOT a true

jelly fishjelly fish

Portuguese Man 0’ WarPortuguese Man 0’ War

Tentacles of Physalia physalis

Portuguese Man o’ War Portuguese Man o’ War vs. Box Jelly fishvs. Box Jelly fish

Class Cubozoa: Box JellyfishClass Cubozoa: Box Jellyfish

Chironex fleckeriChironex fleckerithe Box jelly fishthe Box jelly fish