Vegetative Development - Growth
It is quantitative and irreversible change. It reflects an increase in size and volume of an organism. For example, the change in the size of a leaf or increase in the length or breadth of stem can be referred to as growth. It is usually accomplished by changes in form and shape. There can be growth of the whole plant or only of an organ.
At cellular level there is synthesis of various molecules, especially macromolecules such as nucleic acids, proteins, lipid at the expense of energy derived from catabolism in growing structures. The macromolecules organise into membranes and organelles-chloroplast, mitochondria and others. There is also active division of cells.