Question

Why does plant cell posses a large sized vacuole

Answer 1

Vacuoles in plants are multifunctional organelles. They function as lytic compartments, reservoirs for metabolites, homeostasis, provide hydraulic stiffness etc. After growth, the plant cell has one large central vacuole. The volume of the cell filled by vacuole varies from cell to cell. Sometimes it can occupy more than half of the cell’s volume that is upto 80% of its volume.  
Plant cells have large sized vacuoles because these ghelp the cell in maintaining stiffness while it withstands all the environmental conditions. They store food materials, water required by the plant. Over a period of time the excretory products accumulated will break down in the vacuole. Vacuoles maintain the shape of the cell constantly without getting disturbed by the availability of the water to the plant. Hence, plants have larger vacuoles.
Animals can move from place to place in search of food, water and others while plants cannot.

Answer 2

Explanation:

$\huge\bold\color{red}\star\green{\fbox{Answer}}\star$

• Vacuoles are fluid filled sac like structures.
• In a newly formed plant cell, the vacuoles are small.
• As the cell becomes old, these vacuoles, fuse to form a single large vacuole.
• In mature plant cells the might occupy almost the entire cell space.