What cellular structure is primarily responsible for storing food and water?

The vacuole is primarily responsible for storing food and water within the cell. In plant cells, vacuoles serve as large storage containers that can hold not only water but also nutrients and waste products. They play a crucial role in maintaining turgor pressure, which helps keep the plant upright and firm. Furthermore, vacuoles can store various substances utilized in metabolic processes.

In contrast, the cytoplasm is the jelly-like substance that fills the cell and houses various organelles, but it does not have the specific function of storage. The cell membrane acts as a barrier, controlling the movement of substances in and out of the cell but does not store materials. Ribosomes are the sites of protein synthesis and are fundamental to creating proteins but do not have storage capabilities. Therefore, the specific function of vacuoles in storing food and water makes it the correct answer.