SPONGES AND CNIDARIANS

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SPONGES AND CNIDARIANS
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SPONGES

• Phylum PORIFERA (means having pores)
• Body is pierced all over with PORES
• Take food into their bodies animal kingdom
• No symmetry
• Only specialized cells - lack tissues, organs,
  and organ systems
• Moving water carries food in through the pores
  and removes waste out through the pores.

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EXPLORING A SPONGE
Moving water is the key to a sponges survival.
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SPONGE REPRODUCTION

• SEXUAL REPRODUCTION
• Single sponge both sexes.
• Eggs one time of year.
• Sperm another time of year.
• When a sponge produces sperm the water currents
  carry the sperm to another sponge to fertilize
  the eggs.
• After fertilization, larva develops.
• The sponge larva(hollow ball of cells) will swim
  through the water and eventually attach to a
  surface and grow into a sponge.

• ASEXUAL REPRODUCTION
• BUDDING
• Small new sponges grow from the sides of an adult
  sponge.
• Eventually tiny sponges detach and begin life on
  their own.

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CNIDARIANS

• PHYLUM CNIDARIA
• Cnidarians have stinging cells and take their
  food into a hollow central cavity.
• Jellyfish, sea anemones, and corals.
• Carnivores that use their stinging cells to
  capture prey and to defend themselves.

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CNIDARIAN BODY PLANS

Polyp Hydra, sea anemone, coral Vase shaped,
mouth at top Do not move, attached
Medusa Jellyfish Mouth open downward Adapted for
free swimming.
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CNIDARIANS

• FEEDING
• Stinging cells inject venom that paralyzes prey.
• Tentacles pull animal into its mouth.
• Food is digested in body cavity.
• Digestive system with only one opening,
  undigested food expelled through mouth.

• REPRODUCTION
• Reproduce sexually and asexually.
• Budding most common for Polyps.
• Sexual Reproduction
• some cnidarians are both sexes, others are
  separate sexes.