3 Groups of specialized cells, do not form true tissues or organs Sessile-attached to surfacePores allow water/plankton to circulate (suspension/filter-feeders)AsymmetryChoanocytes – 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
4 Feeding Suspension/Filter feeders-actively filtering food particles Intracellular digestionChoanocytes trap food/pass it onAmebocytes – complete digestion by transporting and storing food particles
5 Respiration, Feeding, Excretion Water circulationdiffusionResponseLacks nervous systemProduce toxins
6 Sexual 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
7 Reproduction – 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 parent
8 Types of SpongesEncrusting-form thin growths on rocks/dead coral (sometimes bright colors)
Your consent to our cookies if you continue to use this website.