PORIFERA
Basic Characteristics:
- Asymmetrical or superficially Radially
- Three cell types: Pinacocytes, Amoebiod (Mesenchyme), and Choanocytes
- Central cavity, or a series of branching chambers that water circulates during filter feeding
- No tissue or organs
- Asymmetrical or superficially Radially
- Three cell types: Pinacocytes, Amoebiod (Mesenchyme), and Choanocytes
- Central cavity, or a series of branching chambers that water circulates during filter feeding
- No tissue or organs
*Cell Types
1.) Pinacocytes: thin, flat cells that line the external surface of a sponges porocytes(specialized pinacocytes), may regulate water circulation
2.) Amoeboid: circulate in the jellylike mesophyl (mesenchyme)
3.) Choanocytes: circulate water throughout the sponge
2.) Amoeboid: circulate in the jellylike mesophyl (mesenchyme)
3.) Choanocytes: circulate water throughout the sponge
*Spicules (Spongin): form the skeleton of the sponge. They also may play a role in defense against predators and these determine the class the sponge is in.
The 3 Major Classes of Spicules
*Body Plan:
uses currents that flow through the sponge to provide food and oxygen
Shape Varieties
*Life Cycle
- Collect food by filtration of the choanocytes and phagocytinization by pinacocytes
- Feed on particles less than 50 microns, amoebocytes distribute food through body
- Monecious (produce egg and sperm) and avoids self-fertilization by timing a gamete production
- Sexual production: production of free-swimming larva that settle on the substrate
- Asexual Production: involves production of gemmules(part of sponge that comes off containing masses of amoeboid cells) are resistant to cold and drying
- Regenerate very well
- Have no nerve cells for communication but do coordinate feeding functions and other activities
- Halting activity of the choanocytes decreases rates of filtration
- Feed on particles less than 50 microns, amoebocytes distribute food through body
- Monecious (produce egg and sperm) and avoids self-fertilization by timing a gamete production
- Sexual production: production of free-swimming larva that settle on the substrate
- Asexual Production: involves production of gemmules(part of sponge that comes off containing masses of amoeboid cells) are resistant to cold and drying
- Regenerate very well
- Have no nerve cells for communication but do coordinate feeding functions and other activities
- Halting activity of the choanocytes decreases rates of filtration