1. Phylum Porifera
The Sponges
Phylum Porifera

2. Phylum Porifera Overview
Most primitive of the multicellular animals
Sponges
Over 7,000 species
2% of all sponges are freshwater, none are terrestrial
None named Bob
Phylum Porifera

3. Phylum Porifera Overview
Sponges occur in shallow water habitats and vary widely in size (up to 1m. high) and shape
All sponges are sessile (non moving) filter feeders.
They feed on small plankton that gets trapped in their pores.
Phylum Porifera

4. Sponge Diversity Rope Sponge Black-ball sponge Yellow Tube Sponge
Phylum Porifera

5. How does a sponge work?
Most sponges work rather like chimneys: they take in water at the bottom and eject it from the osculum ("little mouth") at the top.
Sponges can control the water flow by various combinations of wholly or partially closing the osculum and ostia (the intake pores) and varying the beat of the flagella, and may shut it down if there is a lot of sand or silt in the water.[3]
Phylum Porifera

6. Collar Cells
Choanocytes
Choanocytes: (collar cells) act as a pump to bring water into the sponge
Phylum Porifera

7. Sponge Support
Collagen is found between the inner canals and chambers. Gives the sponge its shape.
Phylum Porifera

8. Spicules
Collagen is stiffened by adding microscopic minerals or additional protein fibers (spongin) or both.
Spicules: skeleton structures, made of calcium carbonate (CaCO3) or silicon dioxide (SiO2).
Spicules
Phylum Porifera

9. Porifera Reproduction
Asexual budding
Regeneration: can regenerate from broken pieces
Sexual
Usually hermaphroditic with male and female cells scattered throughout the connective tissue.
Phylum Porifera

10. Porifera Classification
Phylum Porifera
Class Calcarea
Class Demospongiae
Class Hexactinellida
Phylum Porifera

11. Class Calcarea Have spicules made of calcium carbonate
Mostly small in size (<15 cm.), and form irregular masses
Never contain spongin, restricted to shallow water, and strictly marine
Phylum Porifera

12. Class Demospongiae (Most sponges)
Have spicules made of silicon dioxide (SiO2) or spongin or a combination of both
Most sponges belong to this class (90%)
Mostly found on the continental shelf
Spongia spp. (Bath sponge)
Phylum Porifera

13. Class Hexactinellida (Glass sponges)
Spicules are made of silica
Usually found in deep water on soft substrates in the tropics 200-1,000m.
Spicules are six pointed and have a lattice-like structure
Cup, vase or urn shape
Euplectella (Deep sea Glass sponge)
Phylum Porifera