Cnidarians Ctenophorans copyright cmassengale 1 CNIDARIANS Phylum Cnidaria
- Slides: 43
Cnidarians & Ctenophorans copyright cmassengale 1
CNIDARIANS
Phylum Cnidaria • About 9000 species • Most are marine (jellyfish, coral, sea anemones, Portuguese man-of war) • Hydras are found in freshwater • All have arm-like tentacles
Cnidarian Characteristics • Radial symmetry • Hollow gut -Gastrovascular cavity has single opening (serves as both mouth and anus) • Two tissue layers (diploblastic) • Outer epidermis and inner gastrodermis
Cnidarian Characteristics • Either tubular or bell shaped • Tentacles surround mouth • Only animal with cnidocytes (stinging cells) found in the tentacles • Nematocyst – coiled, harpoon-like stinger inside cnidocyte that shoots out
Cnidarian Characteristics • Cnidocytes contain poison to paralyze prey • Tentacles bring food into mouth • Inner gastrodermis secretes digestive juices into gastrovascular cavity which digests food and circulates nutrients
Extracellular Digestion Food digested outside of cells
Cnidocyte Coiled nematocyst
Nematocyst Barbed, threaded stinger capsule’s lid trigger nematocyst
Cnidarian Systems • Have a simple nerve net & sensory receptors • Muscles help in directional movement & capturing prey
mesoglea-filled bell tentacles Jellylike mesoglea between two cell layers supports cnidarian
Two Main Body Plans of Cnidarians UPRIGHT TENTACLES HANG DOWN epidermis Polyp mouth mesoglea gastrodermis Medusa Mesoglea THICK Mesoglea THIN
Cnidarian Diversity • Scyphozoans: Jellyfish • Anthozoans: Sea anemones Corals • Hydrozoans: Hydra • Cubozoa Box Jellies
Cnidarian Diversity Coral polyps Sea Anemone Jellyfish Coral polyps
Anthozoans
Anthozoan Characteristics Sea Anemones § Brightly colored & Resemble flowers § Solitary polyps § Feed on invertebrates & fish Corals § Most are colonial § Build limestone case § Live as polyps in their case
Sea Anemones & Coral • Exist only as Polyps • Clownfish live in anemone tentacles • Corals build a limestone case which build up & form reefs ANEMONE CORAL
Distribution of Coral Reefs
Hydrozoans
Hydrozoans Hydra • Exist only as polyps • Reproduce by budding • Freshwater only • Form resistant zygotes when environment is bad • Move by somersaulting with tentacles
Hydra
Hydra Feeding
Food in Gastrovascular Cavity
Portuguese man-of-war • Colonial Hydrozoan (not a single organism • Tentacles sting prey such as fish & humans • Polyps in colony feed • Has gas-filled air float
Hydrozoan Life Cycle Most hydrozoans alternate polyp and medusa forms, as in the life cycle of Obelia
Obelia Life Cycle (Hydrozoan) Larva called a planula reproductive polyp male medusa female medusa ovum sperm zygote feeding polyp forming planula Fig. 25 -15 a, p. 411
Cubozoans Box Jelly. Fish
Scyphozoans
Scyphozoan Characteristics Jellyfish • Medusa is dominant body form • Go through small polyp stage during life cycle • Stinging tentacles • May live close to shore or the open ocean
Parts of a Jellyfish
Some Jellyfish Show Luminescence
Jellyfish Life Cycle
CTENOPHORANS
Ctenophoran Characteristics • Called comb jellies • All marine • Approximately 100 species • May be spherical, ovoid, or elongate in appearance • Bioluminescent
Ctenophoran Characteristics • Radial symmetry • Have eight plates of fused cilia that resemble combs • Move by beating cilia • Most of the body is jelly-like mesoglea • Body & tentacles covered with sticky mucus to catch prey
Comb Jelly Anatomy
Beating Cilia Ctenophore: Comb Jelly
Ctenophore 42
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- Radijalna simetrija
- Cmassengale
- Cmassengale
- Copyright
- Characteristics of phylum cnidaria
- Kingdom animalia phylum cnidaria
- Cnideria diagram
- Cndarian
- Phylum cnidaria general characteristics
- Obelia medusa diagram
- Cnidaria and ctenophora
- Hydra coral
- Anemone life cycle
- Are sponges cnidarians
- Section 33-1 review porifera answer key
- Sponges concept map
- Chapter 26 sponges and cnidarians answer key
- 2 body forms of cnidarians
- Porifera level of organization
- Chapter 26 sponges and cnidarians answer key
- Symmetrical face
- Characteristics of cnidarians
- Chapter 24 section 1 animal characteristics answer key
- Cnidoblast
- Chapter 26 sponges and cnidarians answer key
- Sponges types
- Body plan of cnidaria
- Are animals autotrophs or heterotrophs
- Sponges cnidarians and worms
- Define cnidocytes
- Cnidaria
- Anatomi anthozoa
- Porifera cnidaria
- Sistema nervoso dos cnidários
- Cnidaria
- Alat reproduksi coelenterata
- Sciphozoa
- Cnidaria sistema nervioso
- Cnidaria predators
- Reproduction in cnidaria
- Filo celenterados caracteristicas gerais
- No symmetry animals
- Jellyfish
- Major animal phyla