Primary growth refers to the increase in the length of the root and the shoot as a result of division of cells in the apical meristem in the shoot.
Secondary growth on the other hand is the increase in the girth or thickness of the plant as a result of cell division in the lateral meristem.
Meristem is therefore the structure of plant responsible for primary and secondary growth.
Meristem may be classified into two namely; the apical meristem and the lateral meristem. The apical meristem is responsible for primary growth whereas the lateral meristem is responsible for secondary growth.
