Phylum PoriferaSpongesKingdom: AnimaliaPhylum: PoriferaClasses: Hexactinellida Demospongia Calcarea

Phylum PoriferaSponges5,000 living speciesThree Distinct Groups:Hexactinellida (glass sponges)DemospongiaCalcarea (calcareous sponges)Most primitive of all animals

Major Characteristics:Feed by filtering water through their outer walls and pumping it out of bodyFlow of water is uni-directionalGenerally non-motile but can move up to 4 mm per dayAlmost all are marine organismsAmorphous & Assymetrical

Feeding:Flow of water through the sponge allows for feeding, waste removal, and the intake of oxygenA combination of pressure, flagella, and contractile movements pump waterFilter Bacteria as a food source

Moving Water/Current = Low PressureWater pumped in through the walls

Reproduction:Can reproduce sexually and asexuallySexually they release large amounts sperm that are taken in by females of the same speciesSexually they could be hermaphrodites (a boy/girl in the same organism)Asexually they produce buds

Structure / Anatomy: No tissues or organsEach type of sponge cell is responsible for a specific function

Skeletal / Muscular:Opening at top called the osculumGelatinous interior called the mesohylThe interior cavity called the spongocoelOSCULUM - openingMESOHYLSPONGOCOEL

Structure / Anatomy:

Structure / Anatomy:

Spicules:

Skeletal / Muscular:The skeleton is made up of calcium carbonate splinters called spicules and/or a protein based mesh like substance called spongin

Skeletal / Muscular:The structural wall consists of the outer pinacocyte cells, a middle layer of gelatin containg amoebocyte cells, while the interior consists of the collar cells which have flagella

Circulatory:Amoeboid Cells in the wall transport food and nutrients

Excretory:All wastes are purged through the main pore called the osculum

Respiratory / NervousVarious cells take in oxygen through diffusionNo nervous system is present

Digestive:Filter feedersCollar cells engulf and digest food vacuolesUse amoeboid cells to distribute nutrients

Class: HexactinellidaGlass spongesConsists of silica constructed fibers called spiculesCannot contract like other sponges though can send electrical impulses

Class: DemospongiaMost diversity90% of species fall into this classCan consist of spongin and / or silica spicules

Class: CalcareaFound in shallow watersSpicules are composed of calcium

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