Sponges are pretty amazing animals. Their cells work together, but are also pretty independent. Each cell gets its oxygen directly from the water that flows through the sponge all the time. The carbon dioxide leaves the same way. No cell is far from this constant flow. There’s a great video at:

Some of the cells have a flagellum, which is shaped like a hair, but can whip around to move water. Each cell is tiny, but they are powerful working together. They use the flow of water to help them trap the tiny particles of food they eat. They don’t have a digestive system. Each cell breaks down the particles itself.

One amazing result of the cells being independent is that if you push the sponge through a mesh, and break it into tiny pieces, those pieces find each other and make new sponges! Why do you think it’s so uncommon for the cells to be so independent?

If you are interested in questions like these, you may want to study zoology (the study of animals).

Thanks for asking,

Sponges have special cells called collar cells that have undulipodia (flagella) that beat to create a current through the sponge.

We breathe by inhaling; pulling air (that contains oxygen) into our lungs. Sponges do not have lungs, they take oxygen directly into the cells that are in contact with the water. Here is a great article that explains more:
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