Final answer:
Sponges have a porous body with specialized choanocytes that enable efficient water circulation, which facilitates feeding, gas exchange, and excretion, through a unique system of canals and chambers.
Step-by-step explanation:
Sponges, belonging to the phylum Porifera, have a unique body structure that effectively allows water to circulate through them. This adaptation enables them to get oxygen and nutrients to all of their cells. The sponge's body is covered with pores that lead to a system of canals and chambers, facilitating water flow throughout its structure. Moreover, the sponge uses choanocytes, or collar cells, to generate a directed water current through the sponge body. The flagellum of each choanocyte beats to draw water into the sponge, filter out food particles, and assist in the diffusion of oxygen. As water flows through the sponge, it captures food particles and absorbs oxygen, which is then diffused to all cells. The filtered water, now carrying waste products, exits through the osculum. This process allows for efficient feeding, gas exchange, and excretion, which are critical for the sponge's survival.