Porifera (Sponges)

By: Lauren Chapman & Claire Bonney

Tissue Layers & Symmetry

These sponges have radially symmetry. Radially symmetry is when there is an arrangement of parts of an organism around a single main axis. Porifera lack special tissues and when injured, they regenerate the wounded material. They are acoelomate, meaning they have no tissue or organs.  

Excretion, Support, Digestion, Respiration, Reproduction, Circulation, Sensory Processing, & Cognitive Skills

Porifera have an abundant amount of pores and channels that allow the flow of water through them. Water flow systems supports the circulatory, respiratory, digestive, and excretory systems. The water obtains food and oxygen for the sponge and removes wastes. For digestion, they consume materials through phagocytosis (intracellular). Intracellular is when the sponge digests materials through the cytoplasm of the cell. These sponges have three ways of asexual reproduction, fragmentation, budding, and the production of gemmules(survival pods). Only a few amount of species use budding as a way of reproduction. They also reproduce sexually using the water to transport the sperm to a different sponge. Porifera do not have sensory cells, however they will close their ostia (tiny pores) if there is too much certain matter in the water or if they are touched. Therefore they are cognitive because they close up when touched.


These sponges are important in nutrient cycles in coral reef systems. Water quality change is suggested to be a result of these sponges. They also convert nitrogen gas into useful nitrogen that is beneficial to the survival of other organisms.

Interesting Facts

1. The phylum Porifera is entirely aquatic organisms. Most sponges are found in marine environment not in freshwater lakes or streams.

2. Spongebob Squarepants is a Porifera sponge

3. Porifera will partly close their pores when the ocean water is sandy, to prevent sand or dirt entering

4. These sponges can live around 200 years

5. Some of these sponges are carnivorous and eat crustaceans

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