The formation of stable supporting elements has been an important prerequisite for the evolution of large terrestrial organisms. The architectural design of the plant's body of vegetation is very complex.
Thin petioles carry heavy and flat laminas, stems support leaves, flowers and fruits.
All plant organs are exposed to mechanical strains. Organs above ground follow the wind's drift. Their high elasticity lets them either return to their original position, or it makes them swing around an imaginative axis. Trunks are stable enough to resist the wind's pulling. They withstand pressure and are inflexible, although their projecting treetops provide the wind with a large target.