Phylum Porifera contains three main classes of sponges - Calcarea, Hexactinellida, and Demospongiae. Sponges have a gelatinous mesohyle layer and specialized cells including choanocytes, archeocytes, pinocytes and porocytes. Their bodies take different forms including asconoid, syconoid and leuconoid depending on the placement and number of openings.

1. Phylum Porifera

2. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Simple Sponge Morphology

3. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sponge Body Forms

4. Spicule Skeleton of sponge Calcium carbonate Silicon Collagen

5. Archeocyte Amoeboid cells Receive food from choanocytes Differentiate into other cell types

6. Mesenchyme (Mesoglea or Mesohyl) Gelantinous matrix

7. Pinococyte Outer surface of sponge Contractile

8. Choanocyte Flagellated cells One end in mesnchyme Flagella creates water currents Collar traps food Passes food to archeocyte

9. Porocyte Forms a pore

10. Asconoid Sponge Ostium Spongocoel Osculum Porocyte

11. Syconoid Sponge Osculum Ostium Spongocoel Choanocytes Radial Canal Incurrent Canal

12. Syconoid Sponge Spongocoel Ostium Choanocytes Radial Canal Incurrent Canal Scypha ( Grantia) xs

13. Leuconoid Sponge Choanocyte chamber Osculum Incurrent canal Excurrent canal Incurrent pore

14. Class Calcarea Grantia Small Vase shape Spicules of calcium carbonate Straight or 3-4 rays

15. Class Hexactinellida Euplectella Spicules Siliceous 6 rays

16. Class Demospongiae Spongia Spicules Siliceous spongin

18. Physiology

19. Sexual Reproduction Monoecious Both male and female Sperm and egg derived from choanocytes Ciliated larva Swim to new location

20. Budding Fragmentation Gemmule formation -survive freezing Asexual Reproduction Micropyle Spicule