Classification. Class Scyphozoa Jellyfish Class Anthozoa Sea Anemones & Corals Class Hydrozoa - Hydra

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Liliana Wiggins
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1 Phylum Cnidaria

2 Classification Class Scyphozoa Jellyfish Class Anthozoa Sea Anemones & Corals Class Hydrozoa - Hydra

3 General Characteristics Stinging tentacles Arranged in ring around mouth Saclike digestive tract Radial symmetry Nerve net One part stimulated, all parts respond

4 Class Scyphozoa the jellies

5 Class Scyphozoa Medusa and polyp body forms

6 Body composed of epidermis, mesoglea, & gastrodermis Considered plankton Limited locomotion Contraction of muscular ring around medusa Gas exchange occurs by diffusion Sea Nettles Video Monterey Bay Aquarium

8 Feeding Tentacles covered in stinging cells called cnidoblasts Contain nematocysts Coiled threaded with barbs Discharged when mechanically and chemically triggered Most barbs contain paralyzing toxin Once discharged, cannot be reused Tentacles pull food to mouth Food enters gastrovascular cavity Enzymes secreted; extra and intracellular Waste expelled out mouth

12 Feeding (cont.) Sticky mucus on medusa also used to catch food Food sticks to surface Ciliated cells move it to the mouth Moon jelly The moon jelly has one of the weakest stings of any jellyfish. These jellies trap much of their food on the sticky mucus covering their bell, then transport it to their tentacle

13 sexual and asexual phases

the longest animal on earth! Not all reach this size but even the small ones pack a powerful sting!

15 7 ft. Lion's Mane jelly 120 ft. Not only the largest of all jellies but with tentacles that can reach over 100 feet, the lion's mane jelly is the longest animal on earth! Not all reach this size but even the small ones pack a powerful sting! Crystal jelly These seemingly harmless creatures can open their mouths wide enough to swallow jellies half their size. They light up when disturbed. People harvest them for the chemicals that make them glow.

16 Box Jelly (Sea Wasp) Found in shallow waters of N. Australia during summer months of Oct.- Aug. 5 to 25 cm across, with four groups of up to 15 tentacles. Venom from a single creature can kill up to 60 adults. Get stung by one and you have from 30 sec. to 4 min. to get help or die!

17 Class Anthozoa Sea Anemones & Adult polyp stage only Sessile (limited movement) Corals

18 Sea Anemone

19 Some symbiotic relationships--mutualism Sea anemone and clown fish Coral and algae

20 Life cycle Asexually Some split in half Regenerate base pieces Budding Sexually External fertilization in water Internal fertilization Sperm released out of males mouth Enters female and absorbed into ovary Larvae released into water by female

21 zooxanthalle algae

Class Hydrozoa Hydroids Intertidal and subtidal

polyps working together as a single organism Can

dominant Some grow on and coat other ocean

22 Class Hydrozoa Hydroids Intertidal and subtidal areas Some independent Some colonial - many polyps working together as a single organism Can also have medusa forms, although polyp form is dominant Some grow on and coat other ocean animals Hydractinia echinata Hydra oligactis Portuguese Man-of-War

23 Portuguese Man-of-War Hydroid colony Tentacles with stinging cells several meters Four different polyps make up organism The float (pneumatophore) is a single individual and supports the rest of the colony. The tentacles (dactylozooids) are polyps concerned with the detection and capture of food Digestive polyps (gastrozooids) break down the food. Reproduction is carried out by the gonozooids.

25 Portuguese Man-O-War are eaten by sea turtles (loggerheads and leatherbacks), and some fish have symbiotic relationships with the Man-O-War, living among the tentacles

26 Obelia Polyp colonies Dominant asexual polyp stage, but also has medusa stage

29 Phylum Ctenophora (sometimes confused with Jellyfish) Comb jellies 8 rows of fused cili (combs) for movement and feeding One species has nematocysts on tentacles Float near surface Bioluminescent

30 Sea Gooseberry When is a jelly not a jelly at all? When it is a comb jelly. Comb jellies are ctenophores, with rows of iridescent combs instead of stinging tentacles. Gooseberries also have two long tentacles for capturing prey. Comb Jelly

Chapter 7 - Cnidarians. Animals with stinging tentacles, including: jellyfish, corals, sea anemones, and hydra

Chapter 7 - Cnidarians. Animals with stinging tentacles, including: jellyfish, corals, sea anemones, and hydra Chapter 7 - Cnidarians Animals with stinging tentacles, including: jellyfish, corals, sea anemones, and hydra Cnidarians Cnidarians are soft-bodied animals. Have stinging tentacles arranged in circles