1. Sponges
Phylum Porifera

2. Phylum Porifera – Pore Bearers
Water flow
Osculum
Choanocyte
Central cavity
Pores
Spicule
Pore cell
Pore
Epidermal cell
Archaeocyte

3. Groups of specialized cells, do not form true tissues or organs
Sessile-attached to surface
Pores allow water/plankton to circulate (suspension/filter-feeders)
Asymmetry
Choanocytes – collar cells that pump water in with flagella, create currents and trap food particles
Osculum – large opening for water to exit
Feeding, circulation, excretion, respiration
Simple skeleton
Spicules – transparent support structures made of calcium carbonate/silica
Spongin - protein
Amebocytes – mobile cells to secrete spicules and spongin

4. Feeding Suspension/Filter feeders-actively filtering food particles
Intracellular digestion
Choanocytes trap food/pass it on
Amebocytes – complete digestion by transporting and storing food particles

5. Respiration, Feeding, Excretion
Water circulation
diffusion
Response
Lacks nervous system
Produce toxins

6. Sexual Reproduction and Life Cycle
MEIOSIS
Haploid (N)
Diploid (2N)
Sperm from a sponge are released into the surrounding water-Spawning. Water currents carry the sperm to other sponges.
New sponge
Sperm (N)
Mature sponge
Metamorphosis (2N)
Egg (N)
Swimming larva
Larva (2N)
The zygote develops into a free-swimming larva. Water currents carry the larva until it attaches to a surface and grows into a new sponge.
Sperm enter another sponge through pores. The sperm are carried to eggs inside the body wall. Sperm fertilize eggs.
FERTILIZATION

7. Reproduction – Cont. Sexual Reproduction
Gametes-sex cells developed from certain amebocytes (most sponges can produce both)
Asexual Reproduction
Budding-branches or buds break off and grow into separate sponges identical to parent

8. Types of Sponges
Encrusting-form thin growths on rocks/dead coral (sometimes bright colors)

9. Red bearded sponge

10. Glass-anchored in deep-water sediments, lace-like skeleton of fused spicules (ex. Venus Flower Basket)

11. Boring-bore thin channels through calcium carbonate shells such as oysters and coral

12. Coralline/Sclero-calcium carbonate skeleton with spicules and spongin form under its body (first known as fossils)

13. Ecology Symbiotic relationships with bacteria, algae, protists
Habitats