Which cell organelle stores materials such as water, salts, proteins, and carbohydrates?

• A. Vacuole
• B. Chloroplast
• C. Digestive system
• D. Nervous system

Answer: (A)

Storing materials inside cells is the job of storage compartments called vacuoles. A vacuole is a membrane-bound sac that holds water, salts, proteins, and carbohydrates. In plant cells, the large central vacuole stores water and helps keep the cell rigid, which supports the plant’s structure. Some animal cells have smaller vacuoles for nutrient storage or waste removal. Chloroplasts are mainly for photosynthesis and energy-rich molecules, not general storage of these substances. The digestive system and nervous system are organ systems outside the cell, not organelles. So the vacuole best fits the description.