1. Invertebrates
Phylum Porifera

2. There are 2 Types of animals
Vertebrates: Animals with backbones.
Invertebrates: Animals without backbones.
* About 97% of all animal species are inverts.

3. Kingdom Animalia Phylum Porifera
Phylum Porifera (“pore bearers”)
About 5,000 to 10,000 species
Are the simplest multicellular animals
Cells are independent of each other
Rely on water current for food, gas exchange, excretion, & reproduction

4. An Introduction
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5. Porifera Most are marine (saltwater)
Have tiny pores on the surface to allow water to enter & circulate through a series of canals where planktonic organisms are filtered out and eaten

6. Porifera
Planktonic: Describes small organisms that passively float or drift in a body of water.

7. Porifera All are filter feeders:
All are sessile:
Living attached to the bottom or a surface.
All are filter feeders:
Actively filter suspended food from the water

8. Porifera: Anatomy
The outer surface is covered with flat cells and sometimes tube-like pore cells called ostia, which form canals to allow water to enter.
Simple sponges have one large atrium in the center which is also called a spongocoel

9. Fish in Atrium/Spongocoel

10. Porifera: Anatomy Food gets trapped here
Water is pumped into a larger canal lined with collar cells also called Choanocytes, which have a flagellum that creates currents and a collar that traps food.
Food gets trapped here

11. Porifera: Eating
After choanocytes trap food on their collar, and is moved along to the base of the collar
Food is then engulfed by the cell to form a food vacuole, and is digested by enzymes and pH changes
Digested food is passed to amoeboid cells, & distributes it to other cells

12. Porifera: Anatomy
Water leaves through the osculum, a large opening on the top

13. Sponges are Filter Feeders

14. Spongin Spongin: Resistant fibers for support.
Magnified spongin Highly magnified spongin
Spongin: Resistant fibers for support.

15. * Are different shapes & sizes
Porifera: Anatomy
Larger sponges need spicules for support
* Are different shapes & sizes

16. Porifera: Body Forms Considered “simple sponges”
1. Ascon: Simplest & least common body form
Considered “simple sponges”
Porocytes regulate water circulation by contracting
Ostia are the outer openings of porocytes & lead directly to a chamber called the spongocoel.
Choanocytes use their flagellum to move water into the spongocoel, which then exits out the osculum.

17. Ascon Body Form

18. Porifera: Body Forms 2. Sycon is when the sponge wall appears folded
Water enters through openings called dermal pores
Pores contract incurrent canals, and the radial canals leads to the spongocoel
Choanocytes (collar cells) line the radial canals
Water travels from the ostia, through incurrent & radial canals, to the spongocoel, and out the osculum

19. Sycon Body Form

20. Porifera: Body Plan 3. Leucon: Have extensive branched canal system
Considered “Complex Sponges”
Water enters the sponge through ostia and moves through branched incurrent canals, which lead to choanocyte-lined chambers
Canals leading away from the chambers are called excurrent canals
Do NOT have a spongocoel (Atrium)
Have multiple exit points (oscula) for water leaving the sponge
Have increased surface area and filter large volumes of water

21. Leucon Body Form

22. Sponge Reproduction
Many are asexual: branches or buds break off and grow into separate sponges identical to the original one.
* No Sound *

23. *** What are gametes? ***
Sponge Reproduction
Sexually: When both sexes release gametes during the spawning season.
Gametes: Haploid cells (sperm or egg) that functions in
sexual reproduction. The union of 2
gametes of opposite sex produces a zygote.
*** What are gametes? ***

24. Sponge Reproduction
Spawning is the production or depositing of large quantities of eggs and sperm in water.
Frog Spawn
Fish Spawning
Clam Spawning

25. More Sponge Spawning Pics.

26. Sponge Reproduction
Zygote: Diploid Cell produced by the fusion of an egg and sperm. A fertilized egg cell.
sperm
Haploid Cell
Zygote
Diploid Cell

27. Are we monoecious or dioecious?
Sponge Reproduction
Most sponges can produce both male and female gametes in the same individual and is called monoecious
Some are dioecious meaning that they have separate sexes in each individual (either male OR female…not both)
We are DIOECIOUS!
Are we monoecious or dioecious?

28. Sponge Reproduction Once the egg is fertilized, a larva is formed
Larva: Is an immature stage that may undergo a dramatic change in structure before changing to the adult body form
After no more than 2 days of free-swimming existence, the larva settles to the substrate and begins to develop into the adult form
What is “Substrate”?

29. Types of Sponges
Encrusting: form thin brightly colored growths on rocks or dead coral.

30. (example: Venus Flower Basket)
Types of Sponges
Glass sponges: live in deep water & have skeletons of fused silica spiclues.
(example: Venus Flower Basket)

31. Types of Sponges
Boring Sponges: bore thin channels through oyster shells and corals.

32. Types of Sponges
Coralline Sponges: A calcium carbonate skeleton forms under the body. Once thought to be extinct, but have since been found in caves and on steep coral reef slopes.

33. Commercial Importance
Bath Sponges: Harvested & used to
bathe with
Medical: Some act as antibiotics & others have painkilling properties (still researching)

34. Harvesting Sponges
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35. The End.