(i) Support: Stem bears branches, leaves, flowers and fruits.
(ii) Conduction: Stem transports water and minerals from root to leaves.
(iii) Food storage: Plants like Potato, Ginger, Turmeric, Arum store excess food within their modified underground stem.
(iv) Food synthesis: Stems of some herbs carry green pigment. In these stems plants prepare their food by photosynthesis.
(v) Protection: Few plants have spines or thorns on the stem surface. These protect them from predators. Cactus, Rose, Lotus, Wood-apple etc. plants have thorns on their stems.