2 Porifera Sponges Living on Earth for at least 540 million years Most sponges live in the oceanArctic to the tropicsshallow water to depths of several hundred metersThey are dry sponges were use forBathingCleaning
3 Porifera What is a Sponge? Sponges are placed in the phylum Porifera (poh-RIF-ur-uh) which means “pore-bearers.”Sponges have tiny openings, or pores, all over their bodiesSponges are sessile, meaning that they live their entire adult lifeThey have irregular symmetry
4 Porifera Why are sponges considered animals? Sponges are multicellular, heterotrophic, have no cell walls and contain only a few specialized cells.Water flowCollar cells or choanocytes (koh-an-uh-sytz) are cells that use flagella to move a steady current of water through the sponge. Water leaves thru the osculum
5 Porifera: Structure Specialized cells of sponges: Collar cells or choanocytes – Use flagella to move a study current of water through the sponge.Osculum – A large hole at the top of the spongeSpicule – spike-shaped structure made of chalklike calcium carbonate or glasslike silicaAmoebocyte – move around within the walls of the sponge and carry food to other cellsSofter sponges have an internal skeleton made of spongin, a network of flexible protein fibers. These are the sponges used as natural bath sponges.
6 Porifera: DigestionSponges are filter feeders – take microscopic food particles from the water.As water moves through the sponge, food is trapped and engulfed by collar cells (choanocytes) that line the body cavityThen, food gets passed to amebocytes who take the food to the rest of the cells in the body
7 Porifera How do they breathe? Sponges rely on the movement of water through their bodies to carry out body functions:Respiration – oxygen obtained from the waterExcretion – removal of wastes into the water
8 Porifera How do they reproduce? Reproduction can be sexually or asexually.Adults produce gemmules which can withstand harsh conditions and grow into an adult spongeReproduce asexually by regeneration – tear of a piece of sponge and a complete new sponge will appear.Sponges are hermaphrodites – each adult can act as either the female or the male in reproductin.
9 Porifera How important are sponges to the environment? Many sponges are large and have irregular shapes and provide habitatsCommensalism and partnershipsEX: bacteria provide food and oxygen to the sponge while the sponge provides protected area.
10 Porifera Types of Sponges Calcareous sponges Found in shallow waters around the worldSpikes made of calcium carbonate (lime)
11 Porifera Types of Sponges Glass sponges Skeleton consists of crystalline silicon dioxideGenerally found in deep, tropical waters
12 Porifera Types of Sponges Demospongiae (Bath sponges) Skeleton is elastic (spongin) fibersFound in the CaribbeanEncrusting Sponge
14 CtenophoraCtenophores (Greek for “comb-bearers”) have eight “comb rows” of fused cilia arranged along the sides of the animal (red rows)The cilia beat and propel the animal through the water
15 CtenophoraCtenophora are commonly known as comb jellies and are voracious predators50 speciesMost species are planktonic carnivores and transparent which feed on zooplanktonLight-scattering cilia and bioluminescenceLack stinging cells but capture prey by sticky cells called colloblastsFavorite food of sea turtlesLack stinging cells
16 Ctenophora Reproduction Most are hermaphroditic Release egg and sperm in water, where sperm must find the egg to fertilize itFertilized eggs develop through larval stage that hatches into an adult; no medusa stageSea gooseberry
17 Hydras, jellyfishes, sea anemones and corals Phylum CnidariansHydras, jellyfishes, sea anemones and corals
18 Cnidarians What is a cnidarian (ny-DAYR-ee-n)? 10,000 species Soft-bodied, carnivorous animalsStinging tentacles arranged in circles around their mouthsSimplest animals to have radial symmetry and specialized tissues.
19 Cnidarians Specialized cells of cnidarians Cnidocytes – stinging cells that are located along their tentaclesNematocyst – poison-filled, stinging structure that contains a tightly coiled dart.In this picture, a sea anemone captures a fish that has brushed the trigger of the nematocyst. When triggered, the filament inside uncoils and shoots a barb into the animal
20 Cnidarians Form and Function in Cnidarians Simple organisms and only a few cells thickResponses to the environment are carried out by specialized cells and tissues.Life cycle that includes two different-looking stages:Polyp stageMedusa stage
21 Cnidarians Polyp stage Cylindrical body with armlike tentacles. Mouth points upwardPolyps are usually sessile
22 CnidariansMedusa StageMotileBell-shaped bodyMouth on the botton
23 Cnidarians How do Cnidarians feed? After paralyzing its prey, cnidarian pulls the prey through its mouth into its gastrovascular cacity