Transcript Anemones_Corals_Jellyfish

Phylum Cnidaria
Sea Anemones, Jellyfish, & Corals
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I) Cnidarians
A) Phylum Cnidaria
1) Means “to have stingers”
B)
C)
D)
E)
True Tissues
Radial Symmetry
Radial Nerve Net
Partial Digestive Tract
1) Only have one opening
F) Some 10,000 species
known
G) First appeared some
540-650 Million Years3
Ago
II) Morphology
A) Oral surface
1) Where the mouth is
B) Aboral Surface
1) Opposite side of the
mouth
C) Central mouth / anus
surrounded by tentacles
D) Mouth opens to gut
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II) Morphology
E) Nematocysts
1) Cnidae
2) Unique stinging
structure
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II) Morphology
F) Polyp
1) Sac-like attached stage
with mouth & tentacles
orientated upwards
G) Medusa
1) Jellyfish, an upside down
polyp for swimming
H) Some cnidarians go
through both life stages,
others only one
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II) Morphology
I) Epidermis
1) External cell layer
J) Gastrodermis
1) Lines the gut
K) Mesoglea
1) Middle, gelatinous
layer
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III) Feeding
A) Practically all are
carnivores
B) Use nematocysts
primarily to capture prey
1) Some contain toxins
C) Ingest into mouth
D) Extracellular digestion
1) Initial digestion that takes
place outside the cells (in
the gut)
E) Intracellular digestion
1) Final digestion within cells
lining the gut
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IV) Reproduction
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V) Classes of Cnidarians
A) Hydrozoans
1) Leathery or bushy colonies of polyps
2) Siphonphores: drifting colonies of polyps
B) Scyphozoans
1) Jellyfish
2) Larger, bell-shaped medusas
C) Cubozoans
D) Anthozoans
1) Sea Anemones
2) Corals
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A) Hydrozoans
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B) Scyphozoans
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C) Cubozoans
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D) Anthozoans
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D) Anthozoans
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