Which organelle stores water and wastes and is typically large in plant cells?

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

Answer: (A)

The main idea here is that plant cells rely on a large storage compartment to hold water and waste products, supporting both nutrition management and rigidity. This organelle, the vacuole, is a membrane-bound sac that can contain water, ions, sugars, and various small molecules. In mature plant cells, it can occupy a large portion of the cell's interior, pushing the cytoplasm toward the cell wall and creating turgor pressure that helps keep the plant upright. The vacuole’s membrane, the tonoplast, actively regulates what enters and leaves, helping the cell maintain osmotic balance and store wastes safely. This storage and buffering role is what sets it apart from other organelles: the nucleus houses DNA, the cytoplasm/cytosol is the fluid matrix inside the cell, and mitochondria generate energy rather than serve primarily as storage.