Phylum Porifera Introduction • Grade Parazoa Without tissues Without embryonic layer Without localized gonads Totipotent Introduction • Definition Porifera are sessile, suspension feeding , multicellular animals that utilize flagellated cells called choanocytes to circulates water throught a unique system of water canals (Aquferous system) Characters Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Bauplan Support • Spicule calcareous silica spongin Reproduction • Sexual reproduction • Asexual reproduction Gemmule in Spongilidae Reduction body in marine Budding Asexual larvae Asexual reproduction Asexual reproduction Asexual reproduction Asexual reproduction Sexual reproduction Hermaphoditic = Monoecious Protandric Protogyny Gametogeesis Sperm form from choanocyte Ovum form from archaeocyte or choanocyte Fertilization in mesohyl Transfer choanoyte Sexual reproduction Embryology Cleavage is unequal holoblastic Stomoblastult Olynthus Rhagon Embryology Embryology Larval form Amphiblastula =Calcareous Coeloblastula-Stereoblastula=some Calcareous Paranchymula Embryology Embryology Taxonomy Phylum Porifera Subphylum Cellularia ( All member possess distinct choanocyte) Class Demospongia 95% all existing sponge All freshwater Support element silica, spongin or both All leuconoid Class Calcarea All species are marine Spicules composed of calcium carbonat Have three form of complexity Subphylum Symplasma ( Epithelial and choanocyte tissue are syncytial) Class Hexactinellida ( The glass sponge) All have 6- sided spicules of silica Taxonomy Grade Mesozoa Grade Mesozoa • Have some tissue • Have localized gonad • Have some embryonic layer Phylum Placozoa Phylum Monoblastozoa Phylum Rhombozoa Phylum Orthonectida Grade Mesozoa Placozoa Trichoplax adherens Grade Mesozoa Monoblastozoa Salinella Grade Mesozoa Rhombozoa Grade Mesozoa Grade Mesozoa Grade Mesozoa Grade Mesozoa Grade Mesozoa Orthonectida Grade Mesozoa .