There are various methods in plants to get rid of excretory products-

• The excess of water is transpired by transpiration. Transpiration is a phenomenon where moisture is taken up to the leaves from roots and is released into the atmosphere.

• Some plants store waste products in their leaves which are automatically removed when the leaves fall-off.

• Waste products like tannins, resins (in non-functional old xylem) and gums are stored in barks which are eliminated by peeling of the bark.

• Oxygen is produced as a by-product in photosynthesis and carbon dioxide is produced as a result of respiration. These gases are released from stomata in leaves of plants.