1. Phylum Porifera
Dr. Shivani Gupta,
PGGCG-11,
Chandigarh 1

2. General Characters
-Most are marine; a few live in fresh water one family
Spongillidae
-Metazoan, with loosely aggregated cells, therefore no organs or true tissues.
-Asymmetrical or radial symmetry
-Body with pores (ostia and osculum), canals, and chambers through which a water current flows.
-Epidermis of flat pinacocytes;
-Inner surfaces lined with flagellated collar cells (choanocytes)-create water currents

3. General Characters
-matrix called mesohyl contains amebocytes and skeletal elements
-Skeleton of calcareous or siliceous crystalline spicules and/or protein fibers (spongin)
-Digestion intracellular
-Respiration and excretion by diffusion
-Nervous system absent
-All adults sessile and attached to substrate
-Asexual reproduction by buds or gemmules
-Sexual reproduction by eggs and sperm
-Free-swimming ciliated amphiblastula larvae

4. Simple Sponge

5. Sponge Body Forms

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

10. 10

11. 11

13. Figure 12.12a

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

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

17. Classification Class Subclass Calcarea (ii)Calcinea (i) Calcaronea
Hexactinellida
(i)Hexasterophora (ii)Amphidiscophora
Demospongia
(i) Tetractinomorpha (ii)Ceractinomorpha

18. Class Calcarea
-All are marine, single in live in
colony.
-Endoskeleton is composed of spicules made of calcium carbonate.
-Choanocyte cells are large.
-Osculum small surrounded by
spicules.
Examples-Sycon,Leucosolenia, Clathrina, Petrobiona
Leucosolenia
Sycon
Petrobiona
Clathrina

19. Class Hexactinellida -Flowre-vase like body.
-Spicules are composed of silica.
-Choanocytes are restricted to
flagellated chamber.
Example: Euplectella,
Hyalonema
Spicule
Hyalonema
Euplectella 19

20. Class Demospongiae
-Endoskeleton may be formed by siliceous spicules or sponging fibres or both. -Choanaocytes are restricted to spherical chambers. -Spicules are having one to four rays. Examples: Cliona, Poterion, Spongilla, Helichondra
Cliona
Poterion
Spongilla
Helichondra
Spongin fibres
Spicules20

21. Sexual Reproduction -Monoecious
Both male and female
-Sperm and egg derived from choanocytes
-Ciliated larva
Swim to new location 21

22. Asexual Reproduction -Budding -Fragmentation -Gemmule formation
survive freezing
Gemmule 22