How do sponges breathe?

Answer 1

A sponge gets its oxygen from the water. The oxygen moves from the water to the sponge by a process called diffusion. Diffusion is when molecules of a substance move from an area where they are highly concentrated (where there are a lot of oxygen molecules) to an area where they are less concentrated (where there are not a lot of oxygen molecules). Oxygen is more highly concentrated in the water then in the sponge. Therefore, the oxygen goes from the water to the sponge.