1. KINGDOM ANIMALIA Phylum Porifera

2. Sponge History
Evidence suggests that sponges diverged early in the evolution of animals.
555 mya
580 mya

3. Are sponges really animals?
Like other animals, they
are multicellular.
are heterotrophic.
reproduce sexually.
Unlike most other animals, they
do not have a mouth or gut
are sessile as adults.
are not organized beyond the cellular level.

4. Question #1
Which of the following characteristics makes sponges unique among other animals?
They are multicellular.
They are heterotrophic.
They do not have a mouth or gut.
They are capable of reproducing sexually.

5. Sponge Organization
A sponge is organized around its canal system, through which flagellated cells called choanocytes pump water.
The body is supported by an endoskeleton of spongin (a form of collagen) and/or tiny spicules (made of calcium or silica).

6. Question #2
What type of cellular structure does a choanocyte use to help create the current inside a sponge?
cilium
flagellum
spongellium
pseudopodium

7. Question #3
The skeleton of a sponge includes tiny crystal-like structures that are called
spongin
spicules
collagen
choanocytes

8. Canal Systems Three major types:
Asconoid-the simplest type of organization. Small and tube shaped, water enters the sponge through dermal pores and flows into the interior.

9. Asconoid

10. Canal Systems
Syconoid-larger versions of asconoids, still having just a single osculum. However, the body wall is generally thicker and more complex with incurrent canals rather than simple pores.

11. Syconoid

12. Canal Systems
Leuconoid-the most complex in design in that not all the chambers are flagellated.
Water flowing in through incurrent canals is pumped through the chambers and expelled via one of a series of oscula.
Best adapted to increase size.

13. Leuconoid

14. Question #4
Which of the following sponge body types would you expect to find in this sponge from the video?
Asconoid
Syconoid
Leuconoid

15. How do sponges eat? Sponges are suspension feeders.
Water brings in food that is trapped by the choanocytes and transferred to the rest of the sponge by cells called amebocytes.

16. How do sponges eat?
choanocytes
amebocytes

18. Classification There are four classes of sponges:
Calcarea-three- or four-rayed calcareous spicules (calcium carbonate); all three body forms

19. Classification
Hexactinellida-six-rayed siliceous spicules (silica); generally syconoid

20. Classification
Demospongiae-siliceous spicules (silica) that are not six-rayed, if any; all leuconoid

21. Classification
Sclerospongiae-not recognized by all taxonomists. These sponges have siliceous spicules and a massive basal skeleton of calcium carbonate; all leuconoid

22. Question #5
Which of the four classes of sponges includes sponges with both silica and calcium carbonate in their skeletons?
Calcarea
Hexactinellida
Demospongiae
Sclerospongiae

23. Reproduction Asexual Reproduction Sexual Reproduction
Asexual budding can produce new sponges.
Sexual Reproduction
Most sponges are hermaphroditic and can internally fertilize themselves.