Phylum Porifera

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Phylum Porifera

• The sponges

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Defining Characteristics

• No Symmetry
• No Tissues

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Sponges are the simplest animals. Below are the
characteristics of sponges

• No tissues
• No symmetry
• No nervous system
• Sessile cannot move from place to place

• So, what do they have? What can they do?

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Sponges
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Sponges
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Sponges have no tissues, but have 4 kinds of
cells

• Epidermal cells
• skin cells.
• Pore cells
• surround pores
• bring in food oxygen.
• Collar cells
• Use flagella to pull food in through the pores
• Amoebocytes
• aid in digestion reproduction
• produce chemicals.

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Spicules

• Thorn-like projections that provide structural
  support and protection.

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Osculum the opening at the top of the sponge.
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Anatomy
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How Sponges Eat Filter Feeding

• Filter feed take food as it flows past them
• Waste expelled through the osculum.

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How Sponges Reproduce Sexual and Asexual

• Sexual Reproduction
• External Fertilization
• Sponges are hermaphrodites produce sperm and
  eggs, and then release them into the water
• Asexual Reproduction
• Budding small external growths pinch off and
  become new sponges
• Regeneration a fragment of sponge breaks off,
  regenerates into a new sponge.

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Budding

• Notice the new sponge forming in purple and
  breaking away to become a separate individual