Describe various conditions or factors necessary for growth.

(N/A) - The growth of a plant is influenced by a variety of external and internal factors.
- Growth of a plant involves the synthesis of protoplasm,cell division,cell enlargement,and cell differentiation.
- Some of the factors that influence the growth of plants are mentioned below:
- $(a)$ Water: It is the first and foremost requirement for the plants for the enlargement of cells,maintaining the turgidity of growing cells,and for the extension of growth. It also acts as a medium for many enzymatic activities. In water stress conditions,the growth of the plants seems to be retarded.
- $(b)$ Oxygen: It helps in releasing metabolic energy essential for growth activities.
- $(c)$ Nutrients: These act as major raw materials (macro and micro essential elements) for protoplasmic synthesis and also act as a source of energy. Under nutrient-deficient conditions,the growth of the plant is affected.
- $(d)$ Light: It helps in the synthesis of food. It also determines the root and shoot growth. Along with light,gravity also serves as an environmental signal that affects certain phases or stages of growth.
- $(e)$ Temperature: For the normal and appropriate growth of a plant,an optimum temperature range is necessary,i.e.,$25-30^{\circ}C$ (this is because enzymatic reactions are very fast at the optimum temperature range).