Which organelle is primarily responsible for storage and maintaining turgor pressure in plant cells?

• A. Vacuole
• B. Nucleus
• C. Cytoplasm/Cytosol
• D. Chloroplast

Answer: (A)

The main concept is that plant cell rigidity and storage for water-and-solute balance come from the vacuole. The large central vacuole holds water and dissolved substances; as solutes accumulate, water follows by osmosis, filling the vacuole and pressing the cytoplasm against the cell wall. This hydrostatic pressure, called turgor pressure, keeps the cell—and the plant—rigid and helps drive growth. Other organelles have different roles: the nucleus stores genetic material, the cytoplasm is where many metabolic processes occur, and chloroplasts carry out photosynthesis and store certain compounds, but they don’t primarily govern storage and turgor. So the organelle responsible for storage and maintaining turgor pressure is the vacuole.