Why Do Plant Cells Have Bigger Vacuoles Than Animal Cells?

Don LaVange/CC-BY-SA 2.0

Plant cell vacuoles serve the same vital storage functions for nutrients, water and wastes as those in animal cells but are much larger because they also provide structural stiffness in combination with the plant's cell walls. This is why water-starved plants droop; their cells have essentially deflated. If a living but wilted plant once again receives sufficient water, it regains its former stiffness as the vacuoles refill.