1. SPONGES

3. FACTS Phylum Porifera (sponges) Representative Group Sponges
DistinguishingFeatures
Collar Cells
General Habitat
Benthic
Level of Organization
Cellular
Symmetry
Asymmetrical
Body Cavity
None
Digestive Tract
Respiratory Exchange
Body Surface
Circulatory System
Segmentation No

4. Details
5,000-10,000 species
All are multicultural or a group of specialized cells
No tissue or organs
Sessile : at the bottom of the sea
These are deep sea glass sponges retrieved at 1400 feet. Glass sponges are typically very fragile and rarely hold their shape when transported to the surface.

5. BODY STUCTURE When separated they can regroup
Porocytes- flat cells on the surface which form canals allowing H2O to enter the sponge
Choanaocytes/ Collar cells: have a flagellum that creates currents to trap food
Osculum: large opening on top of the sponge
Skeleton: made of spiculus (siliceous or calcareous supporting structures) & spongin (fibers made of protein)

6. How would you define the ‘tissue’ of a sponge, and how is it different from the tissues of other animals?

7. Digestion
Suspension feeder: eats food particles that are suspended in the water.
Filter feeder: sponges actively filter food and oxygen from the water.

8. Continuation on Digestion
There is also those who are
Deposit feeders: which eat dead organic particles, or Detritus,that settle in the bottom of the ocean.

9. Reproduction of Sponges
Asexually: Through budding
Sexually: When the collar cells develop into gametes.
Gametes: there like those of other animals, large, nutrient rich eggs and smaller sperm cells that have flagellum.
Broadcast spawning: when gametes are released into the water.

10. Continuation on Reproduction
The early stages of development take place inside the sponge.
Later a tiny, flagellated sphere of cells is released in water, which is planktonic Larva, called parenchymula larva that settles to the bottom and metamorphosis into the adult sponge.