Answer:
3. Vacuole
Step-by-step explanation:
Plant vacuole is a membrane (tonoplast) bound space which contains sap, water, excretory products and other materials (which are not useful for plants).
- It occupies 90% of the volume of the plant cell.
- Tonoplast, in plants facilitates transport of ion into the vacuole (against the concentration gradient) which causes higher ionic concentration in vacuole than in the cytoplasm.
Some other points:-
- Amoeba have contractile vacuole for osmoregulation and excretory purposes.
- Some protists develop food vacuoles by engulfing food particles.