2SPONGES ARE STRANGE Only meet MINIMUM requirement for Kingdom Animalia Multicellular, eukaryotic cells, heterotrophic, moves at some point in it’s lifeBody contains groups of specialized cells, does not form true tissues or organs
3Phylum Porifera – Pore Bearers Water flowOsculumChoanocyteCentral cavityPoresSpiculePore cellPoreEpidermal cellArchaeocyte
4Sessile-attached to surface Pores allow water/plankton to circulate (suspension/filter-feeders)Choanocytes – collar cells that pump water in with flagella, create currents and trap food particlesOsculum – large opening for water to exitFeeding, circulation, excretion, respirationSimple skeletonSpicules – transparent support structures made of calcium carbonate/silicaSpongin - proteinAmebocytes – mobile cells to secrete spicules and spongin
5Feeding Suspension/Filter feeders-actively filtering food particles Intracellular digestionChoanocytes trap food/pass it onAmebocytes – complete digestion by transporting and storing food particles
6Respiration, Feeding, Excretion Water circulationdiffusionResponseLacks nervous systemProduce toxins
7Sexual Reproduction and Life Cycle MEIOSISHaploid (N)Diploid (2N)Sperm from a sponge are released into the surrounding water-Spawning. Water currents carry the sperm to other sponges.New spongeSperm (N)Mature spongeMetamorphosis (2N)Egg (N)Swimming larvaLarva (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
8Reproduction – Cont. Sexual Reproduction Gametes-sex cells developed from certain amebocytes (most sponges can produce both)Asexual ReproductionBudding-branches or buds break off and grow into separate sponges identical to parentInternal fertilization- Sperm cells drift with current, but must get INSIDE a female sponge body to create a new sponge.
9Symmetry “assymmetrical” or “assymmetry” There is NO OFFICIAL SHAPE/SIZE for a sponge.Pictures that follow will show this.
10Types of SpongesEncrusting-form thin growths on rocks/dead coral (sometimes bright colors)