Where does the bubbles of the sponge comes from?

The bubbles in a sponge come from the tiny pores and channels that are part of its structure, allowing water to flow through. When a sponge is submerged in water, it absorbs the liquid, trapping air within its porous material, which forms bubbles. Additionally, the movement of water through the sponge can create more bubbles as air is mixed in. These bubbles contribute to the sponge's ability to absorb and retain water.