Question

Write the functions of the stem?

Answer 1

Primary functions:

1.  It bears leaves and holds them in such a position so to provide maximum sunlight.
2. The stem conducts water and mineral nutrients from the roots to the leaves, flowers and fruits.
3. The stem conducts organic food from the leaves to the ’ roots and storage organs.
4. It holds flowers in such a position so it facilitates 3. pollination and fertilization.
5. The stem also bears fruits and seeds.

Secondary (or Accessory) functions:

1. Storage: In many species, the stems act as the organs for storage of reserve food material (e.g., rhizome of Ginger, corm of Col ocas la. tubers of Potato, etc.), Sugars (e.g., Sugarcane) and water (e.g., Phylloclade of Opuntia).
2. Synthesis of food: Some modified stems of xerophytic plants are green, flat and leaf like. They perform photosynthesis and help in the synthesis of food. Examples – Opuntia, Muehlenbeckia, Ruscus, Asparagus, etc.
3. Perennation: Underground modified stems of many plants (e.g., Ginger, Curcuma) tide over the unfavourable conditions and help in perennation.
4. Vegetative propagation: In many plants, stems sen e as means of vegetative propagation (e.g.. tubers of Potato, Suckers of Chrysanthemum, corms of Colocasia. etc.)
5. Protection: Some stems bear thorns (e.g., Durcmtai, prickles (e.g., Rosa), etc. to protect the plants from browsing animals.
6. Support: In weak-stemmed plants, the stem branches get modified into tendrils (e.g., Grape vine, Passiflora), thorns (e.g.. Bougainvillea) and hooks (e.g., Artabotrys) to help such plants to climb the support.