Phylum Porifera “Sponges” Kingdom: Animalia Phylum: Porifera   “Sponges” Kingdom: Animalia Phylum: Porifera Classes: Hexactinellida Demospongia Calcarea

Phylum Porifera Sponges 5,000 living species Three Distinct Groups: Hexactinellida (glass sponges) Demospongia Calcarea (calcareous sponges) Most primitive of all animals

Major Characteristics: Feed by filtering water through their outer walls and pumping it out of body Flow of water is uni-directional Generally non-motile but can move up to 4 mm per day Almost all are marine organisms Amorphous & Assymetrical

Moving Water/Current = Low Pressure Water pumped in through the walls Feeding: Moving Water/Current = Low Pressure Flow of water through the sponge allows for feeding, waste removal, and the intake of oxygen A combination of pressure, flagella, and contractile movements pump water Filter Bacteria as a food source Water pumped in through the walls

Reproduction: Can reproduce sexually and asexually Sexually they release large amounts sperm that are taken in by females of the same species Sexually they could be hermaphrodites (produce male and female gametes) Asexually they produce buds

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

Skeletal / Muscular: Opening at top called the osculum Gelatinous interior called the mesohyl The interior cavity called the spongocoel OSCULUM - opening SPONGOCOEL MESOHYL

Structure / Anatomy:

Structure / Anatomy:

Spicules:

Skeletal / Muscular: The skeleton is made up of calcium carbonate or silica 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 / Nervous Various cells take in oxygen through diffusion No nervous system is present

Digestive: Filter feeders NO GVC – food is digested intracellularly Collar cells engulf and digest food vacuoles Use amoeboid cells to distribute nutrients

Porifera body structure. Colour-coding:. Yellow: pinacocytes Porifera body structure. Colour-coding: *Yellow: pinacocytes *Red: choanocytes *Grey: mesohyl * Pale blue: water flow Structure types: Left: asconoid *Middle: syconoid *Right: leuconoid

Class: Hexactinellida Glass sponges Consists of silica constructed fibers called spicules Cannot contract like other sponges though can send electrical impulses

Class: Demospongia Most diversity 90% of species fall into this class Can consist of spongin and / or silica spicules

Class: Calcarea Found in shallow waters Spicules are composed of calcium carbonate