Plant architecture is the outcome of several successive developmental processes that can be classified into two events: Organogenesis and extension. Organogenesis stems from the meristems (stem cells) that give rise to different types of organs (e.g., leaves and flowers) and axillary buds, plus the subtending internodes. These organs form a functional unit called phytomer. It iterates and extends itself for several rounds until the apex either aborts or terminates into a specialized structure.