Which structure is responsible for the movement of liquid past anchored cells in multicellular organisms?

The structure responsible for the movement of liquid past anchored cells in multicellular organisms is the flagellum. Flagella are long, whip-like appendages that can propel cells and move fluids around them. In multicellular organisms, flagella can be found in specialized cells, such as sperm cells, where they facilitate the movement through fluid environments.

In addition to their role in individual cell movement, flagella can also help generate flow in a liquid medium, assisting the movement of fluids across surfaces of cells that are immobilized or anchored. This mechanism plays an important role in various biological processes, such as the movement of mucus in the respiratory tract or the flow of fluids in the reproductive systems.

The other structures listed do not have the primary function of moving liquids. Vacuoles primarily store substances and maintain turgor pressure in plant cells. Chloroplasts are involved in photosynthesis and energy production, while ribosomes are responsible for protein synthesis. Therefore, none of these play the same role in fluid movement as flagella do.