1. Phylum Porifera

2. General Characteristics
SPONGES!
Simplest of all animals
_________________
No true tissues or organs
_________________________
Marine and Freshwater
Saltwater are colorful
Freshwater are dull green color

3. General Characteristics Cont.
Sponges are sessile as adults
Free swimming larval stage called dipleurula
Porifera means pore-bearing
Water enters through pores bringing in food and oxygen
____________________________
Osculum- large opening at the top where excess water leaves

4. Water Flow Through the Sponge
WATER OUT
Water Flow Through the Sponge
WATER IN
Osculum

5. 3 Basic Cell Types
_______________
Mesenchyme Cells
Choanocytes

6. 3 Basic Cell Types
1. Pinacocytes- flat cells that line the outer surface of the sponge.
May be slightly contractile
____________: a specialized type of pinacocyte; are tube-like in shape; contractile; and can regulate water circulation.

7. 2. Mesenchyme Cells- move around in the mesohyl layer; are specialized for reproduction, secreting the skeleton, transporting/storing food.
____________: jelly-like layer just underneath the pinacocyte layer.

8. 3. Choanocytes- flagellated cells that line the inner chamber of the sponge; called collar cells.
Flagellum: flagella spins to create water currents to pull in water and food
Collar: __________________________ (plankton) from the water

9. Choanocyte
Choanocyte

10. __________________________
Consists of either one or all of the following:
Spicule: microscopic needle-like spikes that are made of Calcium carbonate (CaCO3) or silica (glass).
Spongin: a fibrous protein made of collagen

11. Sponge Skeletons
Silica Spicules
Limestone Spicules
SPONGIN

12. Sponge Body Types
3 Kinds-
Ascon
__________
Leucon

13. Ascon
____________________
Are vase-like
Least common type of sponge

14. ________________
Sponge wall is folded into canals
Choanocytes line the
radial canals to
move water

15. Leucon Have an extensively branched canal system.
___________________________
Multiple ostia
for water to exit
Increased surface
area means more
water can move
through sponge

16. Body Forms Summary

17. Reproduction
Sexual Reproduction- sponges are monoecious (male and female in the same body)
Release sperm and eggs into the water from the Osculum
Cross-Fertilization takes place in the ocean
_____________________________

18. Sponge Releasing Eggs & Sperm
Reproduction
Sponge Releasing Eggs & Sperm

19. Reproduction Cont’
Sponges can regenerate (regrow) lost body parts through mitotic cell division (asexual)
Sponges also reproduce asexually by ________________

20. Reproduction Cont’d
gemmule
Asexual Reproduction- involves the formation of gemmules
______________: resistant capsules that sponges release to survive unfavorable conditions.
When conditions become favorable, the gemmules sprout into sponges.

21. _____________________
Phylum Porifera
3 Classes
Class Calcarea
Class Hexactinellida
Class Demospongiae

22. Class Calcarea Spicules made of Calcium Carbonate
Can have all three body forms
__________________
Ex. Grantia

23. Class Hexactinellida ___________________________
Can have syncon or leucon body forms
Often fused into an intricate lattice
Glass sponges

24. Class Demospongiae Spicules made of silica, spongin, or both.
____________________
Ex: common bath sponge