Respiration and Digestion

Each cell in a sponge 'breathes' independently and as a result, sponges can maintain about 68% to 99% of the useful matter that they intake. In terms of oxygen, 75% of oxygen is maintained from the water that passes through them. Essentially, sponges breathe in a number of steps:

1. Water comes into contacts with the sponge.
2. The water is absorbed through the pores on the outer layer of the sponge.
3. Flagellated structures absorb the oxygen and then pass it over to the archaoecytes which function as any type of cell.
4. The archaoecytes transport the oxygen to other areas of the sponge through canals; the rest is immediately absorbed through the cell membranes.
5. Water and gases that are no longer needed are pumped through the atrial cavity and out the osculum.

The type of respiration that a sponge utilizes is also known as osmosis.

Water enters by the sponge's pores and flows through chambers called flagellated chambers. The chambers are named this because every cell that lines them have a flagellum, a long thread that whips around to help the water flow. As no. 5 states, when water and such has served it's purpose, it leaves the sponge through the osculum.