The processes that are involved in growth are:
The process of increase in size, mass or height of an individual is known as growth. It can occur by cell division or cell expansion. During this process, there can be a change in the size, dry weight, mass or number of cells in the organism. It is a permanent and irreversible change. Increase in mass and increase in number of individuals are twin characters of growth.
There are three processes that are involved during growth: cell division, cell enlargement and secretion of apoplasmic substances. Cell division is the process of formation of daughter cells from the parent cell. Cell enlargement is the process of increase in the size of the cell due to uptake of the material from the outside. Apoplasmic substances are the non-living materials formed by the cell. For example, cell wall, bone matrix, fibers. During growth, cells secrete the apoplasmic substances.